The prognostic significance of Gleason scores in metastatic prostate cancer

Exploring the role of differentially expressed metabolic genes and their mechanisms in bone metastatic prostate cancer

Background

Approximately 10-20% of patients diagnosed with prostate cancer (PCa) evolve into castration-resistant prostate cancer (CRPC), while nearly 90% of patients with metastatic CRPC (mCRPC) exhibit osseous metastases (BM). These BM are intimately correlated with the stability of the tumour microenvironment.

Purpose

This study aspires to uncover the metabolism-related genes and the underlying mechanisms responsible for bone metastatic prostate cancer (BMPCa).

Methods

Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets of PCa and BM were analyzed through R Studio software to identify differentially expressed genes (DEGs). The DEGs underwent functional enrichment via Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO), with key factors screened by a random forest utilized to establish a prognostic model for PCa. The study explored the relationship between DEGs and the stability of the immune microenvironment. The action and specificity of CRISP3 in PCa was validated through western blot analysis, CCK-8 assay, scratch assay, and cellular assay.

Results

The screening of GEO and TCGA datasets resulted in the identification of 199 co-differential genes. Three DEGs, including DES, HBB, and SLPI, were selected by random forest classification model and cox regression model. Immuno-infiltration analysis disclosed that a higher infiltration of naïve B cells and resting CD4 memory T cells occurred in the high-expression group of DES, whereas infiltration of resting M1 macrophages and NK cells was greater in the low-expression group of DES. A significant infiltration of neutrophils was observed in the high-expression group of HBB, while greater infiltration of gamma delta T cells and M1 macrophages was noted in the low-expression group of HBB. Resting dendritic cells, CD8 T cells, and resting T regulatory cells (Tregs) infiltrated significantly in the high-expression group of SLPI, while only resting mast cells infiltrated significantly in the low-expression group of SLPI. CRISP3 was established as a critical gene in BMPCa linked to DES expression. Targeting CRISP3, d-glucopyranose may impact tumour prognosis. During the mechanistic experiments, it was established that CRISP3 can advance the proliferation and metastatic potential of PCa by advancing epithelial-to-mesenchymal transition (EMT).

Conclusion

By modulating lipid metabolism and maintaining immunological and microenvironmental balance, DES, HBB, and SLPI suppress prostate cancer cell growth. The presence of DES-associated CRISP3 is a harbinger of unfavorable outcomes in prostate cancer and may escalate tumor proliferation and metastatic capabilities by inducing epithelial-mesenchymal transition.

Development and validation of a multivariable prognostic model in de novo metastatic castrate sensitive prostate cancer

BACKGROUND

Metastatic castrate sensitive prostate cancer (mCSPC) is a heterogeneous disease state with variable prognosis. Although several life-prolonging systemic agents are available, there is no robust multivariable model to predict prognosis and improve risk stratification in mCSPC. The objective of this study was to build and validate a multivariable prognostic model to predict overall survival (OS) in mCSPC.

METHODS

We used data from LATITUDE, a phase III randomized controlled trial in which men with de novo mCSPC were randomly allocated to either ADT plus abiraterone or ADT with placebo. Patients with non-missing data (n = 1,058) were randomly split in a 70:30 ratio to training (n = 743) and testing (n = 315) sets. Elastic net regression was used for variable selection. A multivariable Cox regression model for OS was then fitted using the selected variables. The predictive accuracy of the model was assessed on the testing set using the time-dependent area under curve (tAUC) with bootstrapped confidence intervals [CI] primarily for OS and secondarily for radiographic progression-free survival (rPFS).

RESULTS

The 11 prognostic variables in the final model were performance status, number of skeletal metastases, Gleason score, presence of liver metastasis, worst pain score, albumin, lactate dehydrogenase, prostate-specific antigen, hemoglobin, and treatment regimen. The tAUC for predicting OS at 2- and 3-years was 0.74 (95% CI, 0.67-0.80) and 0.72 (95% CI, 0.65-0.77), respectively. The tAUC for rPFS at 2- and 3-years was 0.72 (95% CI, 0.65-0.77) and 0.77 (95% CI, 0.70-0.82), respectively.

CONCLUSIONS

A prognostic model for men with de novo mCSPC was developed and validated in an independent testing set. Our model had high accuracy for predicting OS and rPFS. The model includes commonly used clinical and laboratory parameters and can guide risk stratification of these patients for participation in future trials.

The Potential Tumor-Suppressor DHRS7 Inversely Correlates with EGFR Expression in Prostate Cancer Cells and Tumor Samples

Simple Summary

Prostate cancer is one of the most common malignancies in men. Current therapies are initially effective but resistance often develops, leading to tumor recurrence and death. Further research on new players, mechanisms involved in prostate cancer, and therapy resistance is needed. We studied the role of DHRS7, a potential tumor suppressor with currently unknown physiological function, in prostate cancer cells using proteome and gene expression analyses. Despite the fact that DHRS7 can inactivate 5α-dihydrotestosterone, its effect on prostate cancer cells seems to be unrelated to androgen metabolism. When comparing three widely studied prostate cancer cell lines, we observed a negative correlation between DHRS7 and EGFR expression. DHRS7 knockdown enhanced EGFR expression, while knockdown of EGFR tended to increase DHRS7 expression. Importantly, DHRS7 expression negatively correlates with EGFR expression and positively with survival rates in prostate cancer patients. This study suggests a tumor-suppressor role for DHRS7 by modulating EGFR expression in prostate cancer.

Abstract

Prostate cancer (PCa), one of the most common malignancies in men, typically responds to initial treatment, but resistance to therapy often leads to metastases and death. The dehydrogenase/reductase 7 (DHRS7, SDR34C1) is an “orphan” enzyme without known physiological function. DHRS7 was previously found to be decreased in higher-stage PCa, and siRNA-mediated knockdown increased the aggressiveness of LNCaP cells. To further explore the role of DHRS7 in PCa, we analyzed the proteome of LNCaP cells following DHRS7 knockdown to assess potentially altered pathways. Although DHRS7 is able to inactivate 5α-dihydrotestosterone, DHRS7 knockdown did not affect androgen receptor (AR) target gene expression, and its effect on PCa cells seems to be androgen-independent. Importantly, proteome analyses revealed increased expression of epidermal growth factor receptor (EGFR), which was confirmed by RT-qPCR and Western blotting. Comparison of AR-positive LNCaP with AR-negative PC-3 and DU145 PCa cell lines revealed a negative correlation between DHRS7 and EGFR expression. Conversely, EGFR knockdown enhanced DHRS7 expression in these cells. Importantly, analysis of patient samples revealed a negative correlation between DHRS7 and EGFR expression, both at the mRNA and protein levels, and DHRS7 expression correlated positively with patient survival rates. These results suggest a protective role for DHRS7 in PCa.

Prognostic differences among Grade Group 4 subgroups in robotic‐assisted radical prostatectomy

Objectives

To investigate whether the International Society of Urological Pathology Grade Group 4 (GG 4) subgroups have different oncological outcomes in Japanese prostate cancer (PCa) patients undergoing robotic‐assisted radical prostatectomy (RARP).

Patients and Methods

We conducted a retrospective multicentre cohort study in PCa patients undergoing RARP at 10 institutions in Japan. Pre‐ and post‐operative variables were collected from enrolled patients. We evaluated biochemical recurrence and clinical and pathological variables in the different GG 4 subgroups.

Results

A total of 3195 patients were enrolled in the study. Among them, 298 patients with GG 4 tumours (pathological Gleason scores [GSs] of 3 + 5 [N = 37], 4 + 4 [N = 257] and 5 + 3 [N = 4]) based on RARP specimens were analysed. The median follow‐up period was 25.2 months. The 3‐year biochemical recurrence (BCR)‐free survival (BCRFS) rate in the overall population was 74.5%. The 3‐year BCRFS rates in the pathological GS 3 + 5, GS 4 + 4 and GS 5 + 3 subgroups were 93.8%, 71.9% and 50.0%, respectively (P = 0.01). In multivariate analysis, pathological GS based on RARP specimens, PSA levels at surgery, pathological T stage, pathological N stage and surgical margins were independent risk factors significantly associated with BCRFS. In particular, patients with pathological GSs 4 + 4 and 5 + 3 were at higher risk of BCR than patients with pathological GS 3 + 5 (hazard ratio 4.54, P = 0.03 and hazard ratio 11.2, P = 0.01, respectively). The study limitations include the lack of central pathological specimen evaluation.

Conclusions

For patients with localized PCa undergoing RARP, pathological GS 4 + 4 and GS 5 + 3 were significantly associated with worse BCRFS than pathological GS 3 + 5. Pathological GS 3 + 5 may be overrated in GG 4. This observation emphasizes that primary and secondary GS should be considered to accurately stratify the risk of BCR after RARP.

Impact of Gleason pattern 5 on prognosis for newly diagnosed metastatic hormone-sensitive prostate cancer with Gleason score ≥8

OBJECTIVE

We evaluated the impact of Gleason pattern 5 presence on prognosis among de novo metastatic hormone-sensitive prostate cancer patients with a Gleason score ≥8.

METHODS

The data of 559 patients diagnosed as metastatic hormone-sensitive prostate cancer with a Gleason score ≥8, who were initially treated with androgen deprivation therapy from 2008 to 2016, were retrospectively collected. Patients were divided into two groups as high and low volume based on the CHAARTED trial criteria.

RESULTS

The median overall survival of the 559 metastatic hormone-sensitive prostate cancer patients with Gleason score ≥8 was 70 months, with a median follow-up period of 36 months. Gleason pattern 5 was confirmed in 341 patients (61.0%), in which primary Gleason pattern 5 was confirmed in 164 patients (29.3%). The number of patients with high metastatic volume group was 363 (64.9%). In total and high metastatic volume groups, hemoglobin and lactate dehydrogenase were significant factors for predicting overall survival, but both Gleason pattern 5 and primary Gleason pattern 5 did not show a statistically significant difference. In the low-volume metastatic group, the median overall survival in patients with or without primary Gleason pattern 5 was 40 and 78 months, respectively. In multivariate analysis, only primary Gleason pattern 5 was an independent predictive factor for overall survival in the low-volume metastatic group (hazard ratio 2.76, 95% confidence interval 1.88-8.67; P = 0.0026).

CONCLUSION

The presence of Gleason pattern 5 was not associated with overall survival in metastatic hormone-sensitive prostate cancer with a Gleason score ≥8. In low-metastatic volume metastatic hormone-sensitive prostate cancer, primary Gleason pattern 5 was a poor prognostic factor, which might show a separate treatment option for this group.

Radiomics for Identification and Prediction in Metastatic Prostate Cancer: A Review of Studies

Metastatic Prostate Cancer (mPCa) is associated with a poor patient prognosis. mPCa spreads throughout the body, often to bones, with spatial and temporal variations that make the clinical management of the disease difficult. The evolution of the disease leads to spatial heterogeneity that is extremely difficult to characterise with solid biopsies. Imaging provides the opportunity to quantify disease spread. Advanced image analytics methods, including radiomics, offer the opportunity to characterise heterogeneity beyond what can be achieved with simple assessment. Radiomics analysis has the potential to yield useful quantitative imaging biomarkers that can improve the early detection of mPCa, predict disease progression, assess response, and potentially inform the choice of treatment procedures. Traditional radiomics analysis involves modelling with hand-crafted features designed using significant domain knowledge. On the other hand, artificial intelligence techniques such as deep learning can facilitate end-to-end automated feature extraction and model generation with minimal human intervention. Radiomics models have the potential to become vital pieces in the oncology workflow, however, the current limitations of the field, such as limited reproducibility, are impeding their translation into clinical practice. This review provides an overview of the radiomics methodology, detailing critical aspects affecting the reproducibility of features, and providing examples of how artificial intelligence techniques can be incorporated into the workflow. The current landscape of publications utilising radiomics methods in the assessment and treatment of mPCa are surveyed and reviewed. Associated studies have incorporated information from multiple imaging modalities, including bone scintigraphy, CT, PET with varying tracers, multiparametric MRI together with clinical covariates, spanning the prediction of progression through to overall survival in varying cohorts. The methodological quality of each study is quantified using the radiomics quality score. Multiple deficits were identified, with the lack of prospective design and external validation highlighted as major impediments to clinical translation. These results inform some recommendations for future directions of the field.

Multi-Dimensional Scaling Analysis of Key Regulatory Genes in Prostate Cancer Using the TCGA Database

Prostate cancer (PC) is a polygenic disease with multiple gene interactions. Therefore, a detailed analysis of its epidemiology and evaluation of risk factors can help to identify more accurate predictors of aggressive disease. We used the transcriptome data from a cohort of 243 patients from the Cancer Genome Atlas (TCGA) database. Key regulatory genes involved in proliferation activity, in the regulation of stress, and in the regulation of inflammation processes of the tumor microenvironment were selected to test a priori multi-dimensional scaling (MDS) models and create a combined score to better predict the patients' survival and disease-free intervals. Survival was positively correlated with cortisol expression and negatively with Mini-Chromosome Maintenance 7 (MCM7) and Breast-Related Cancer Antigen2 (BRCA2) expression. The disease-free interval was negatively related to the expression of enhancer of zeste homolog 2 (EZH2), MCM7, BRCA2, and programmed cell death 1 ligand 1 (PD-L1). MDS suggested two separate pathways of activation in PC. Within these two dimensions three separate clusters emerged: (1) cortisol and brain-derived neurotrophic factor BDNF, (2) PD-L1 and cytotoxic-T-lymphocyte-associated protein 4 (CTL4); (3) and finally EZH2, MCM7, BRCA2, and c-Myc. We entered the three clusters of association shown in the MDS in several Kaplan-Meier analyses. It was found that only Cluster 3 was significantly related to the interval-disease free, indicating that patients with an overall higher activity of regulatory genes of proliferation and DNA repair had a lower probability to have a longer disease-free time. In conclusion, our data study provided initial evidence that selecting patients with a high grade of proliferation and DNA repair activity could lead to an early identification of an aggressive PC with a potentials for metastatic development.

A Novel Splice Variant of the Inhibitor of Growth 3 Lacks the Plant Homeodomain and Regulates Epithelial-Mesenchymal Transition in Prostate Cancer Cells

Inhibitor of growth 3 (ING3) is one of five members of the ING tumour suppressor family, characterized by a highly conserved plant homeodomain (PHD) as a reader of the histone mark H3K4me3. ING3 was reported to act as a tumour suppressor in many different cancer types to regulate apoptosis. On the other hand, ING3 levels positively correlate with poor survival prognosis of prostate cancer (PCa) patients. In PCa cells, ING3 acts rather as an androgen receptor (AR) co-activator and harbours oncogenic properties in PCa. Here, we show the identification of a novel ING3 splice variant in both the human PCa cell line LNCaP and in human PCa patient specimen. The novel ING3 splice variant lacks exon 11, ING3∆ex11, which results in deletion of the PHD, providing a unique opportunity to analyse functionally the PHD of ING3 by a natural splice variant. Functionally, overexpression of ING3Δex11 induced morphological changes of LNCaP-derived 3D spheroids with generation of lumen and pore-like structures within spheroids. Since these structures are an indicator of epithelial-mesenchymal transition (EMT), key regulatory factors and markers for EMT were analysed. The data suggest that in contrast to ING3, ING3Δex11 specifically modulates the expression of key EMT-regulating upstream transcription factors and induces the expression of EMT markers, indicating that the PHD of ING3 inhibits EMT. In line with this, ING3 knockdown also induced the expression of EMT markers, confirming the impact of ING3 on EMT regulation. Further, ING3 knockdown induced cellular senescence via a pathway leading to cell cycle arrest, indicating an oncogenic role for ING3 in PCa. Thus, the data suggest that the ING3Δex11 splice variant lacking functional PHD exhibits oncogenic characteristics through triggering EMT in PCa cells.

Prostate Adenocarcinoma with Brain Metastasis: A Surveillance, Epidemiology, and End Results Database Analysis 2010-2015

Background

Prostate adenocarcinoma rarely metastasize to the brain. The aim of this study was to understand the risk association and survival outcomes comparing prostate cancer with brain metastasis (group 1) with prostate cancer without brain metastasis (group 2) at the time of initial diagnosis.

Material/Methods

We searched the Surveillance, Epidemiology, and End Results (SEER) statewide cancer registries for all cases of stage IV prostate cancer adenocarcinoma diagnosed between 2010 and 2015. We used the Kaplan-Meier method and Cox regression to analyze survival outcomes and logistic regression to study the association between the presence of brain metastasis and potential risk variables. Exclusion criteria were the presence of neuroendocrine and small cell histology.

Results

The study included 14 753 patients. Of these, 187 patients were in group 1 (with brain metastasis) and 14 566 were in group 2 (without brain metastasis). When comparing the metastases distribution at the time of initial presentation between group 1 and group 2, the occurrence of bone metastasis was similar in the 2 groups (87% vs 90%); however, liver metastasis (13% vs 4%) and lung metastasis (29% vs 7%) were significantly higher in group 1. We found a strong association between brain metastasis and visceral metastasis. There was no association between age, race, and grade and having brain metastasis.

Conclusions

Our analysis shows that visceral metastasis is associated with a higher risk of brain metastasis. Presence of a visceral metastasis can be a useful parameter to consider early magnetic resonance imaging of the brain to facilitate diagnosis of asymptomatic brain metastasis.

Pathology grade influences competing mortality risks in elderly men with prostate cancer

BACKGROUND

Recent guidelines recommend active management of prostate cancer (CaP), especially high-risk disease, in elderly men. However, descriptive data from a large cohort with extended follow up on the risk of death from CaP in men diagnosed over 70 years of age and its relationship to Gleason score (GS) and serum prostate specific antigen (PSA) level is lacking. Using the Surveillance, Epidemiology, and End Results database, we evaluated the influence of GS and serum PSA levels on the risks of mortality from PC (PCM) and mortality from other causes in localized (LPC) and metastatic (MPC) disease in elderly population.

METHODS

Men diagnosed with PC over 70 years of age between 2004 and 2016 were divided into LPC and MPC groups, categorized by age: 70-74, 75-79, 80-84, 85-89, and ≥90 years and stratified by GS <7, 7, and >7, and serum PSA level <4, 4-10, 10-20, 20-50, and >50 ng/mL. Competing risk estimates for PCM and mortality from other causes were generated for both groups.

RESULTS

Of the 85,649 men, 85.5 % were LPC at diagnosis. Overall, at a median follow up of 4 years, 15% of the men had died including a third from PC. While <15% of men with GS ≤7 died from PC, the PCM was >30% in men with GS >7 in LPC group, which accounted for almost half of total deaths for age 70-84 years. The GS >7 was also significantly associated with PCM in men with MPC. Furthermore, PCM directly correlated with serum PSA levels, with mortality rates reaching up to 50% and 70% for PSA >50 ng/dl for LPC and MPC, respectively.

CONCLUSIONS

There is a substantial risk of dying in men diagnosed with LPC over 70 years of age with GS >7 or a serum PSA >20 ng/mL. Furthermore, the risk for death for MPC directly correlated with GS with PCM increasing from 10%-30% for GS ≤7 to >50% for GS >7. The data, in conjunction with other clinical parameters such as comorbidities could be used to counsel elderly men on management options of PC for both localized and metastatic PC.

Cribriform architecture in radical prostatectomies predicts oncological outcome in Gleason score 8 prostate cancer patients

The Gleason score is an important parameter for clinical outcome in prostate cancer patients. Gleason score 8 is a heterogeneous disease including Gleason score 3 + 5, 4 + 4, and 5 + 3 tumors, and encompasses a broad range of tumor growth patterns. Our objective was to characterize individual growth patterns and identify prognostic parameters in Gleason score 8 prostate cancer patients. We reviewed 1064 radical prostatectomy specimens, recorded individual Gleason 4 and 5 growth patterns as well as presence of intraductal carcinoma, and evaluated biochemical recurrence- and metastasis-free survival. Gleason score 8 disease was identified in 140 (13%) patients, of whom 76 (54%) had Gleason score 3 + 5, 46 (33%) 4 + 4, and 18 (13%) 5 + 3 disease. Invasive cribriform and/or intraductal carcinoma (n = 87, 62%) was observed more frequently in Gleason score 4 + 4 (93%) than 3 + 5 (47%; P < 0.001) and 5 + 3 (44%; P < 0.001) patients. Gleason pattern 5 was present in 110 (79%) men: as single cells and/or cords in 99 (90%) and solid fields in 32 (29%) cases. Solid field pattern 5 coexisted with cribriform architecture (23/32, 72%) more frequently than nonsolid pattern 5 cases (36/78, 46%, P = 0.02). In multivariable analysis including age, prostate-specific antigen, pT-stage, surgical margin status, and lymph node metastases, presence of cribriform architecture was an independent parameter for biochemical recurrence-free (hazard ratio (HR) 2.0, 95% confidence interval (CI) 1.0-3.7; P = 0.04) and metastasis-free (HR 3.5, 95% CI 1.0-12.3; P = 0.05) survival. In conclusion, invasive cribriform and/or intraductal carcinoma occurs more frequently in Gleason score 4 + 4 prostate cancer patients than in Gleason score 3 + 5 and 5 + 3, and is an independent parameter for biochemical recurrence and metastasis. Therefore, cribriform architecture has added value in risk stratification of Gleason score 8 prostate cancer patients.

SFMBT2-Mediated Infiltration of Preadipocytes and TAMs in Prostate Cancer

Infiltration of diverse cell types into tumor microenvironment plays a critical role in cancer progression including metastasis. We previously reported that SFMBT2 (Scm-like with four mbt domains 2) regulates the expression of matrix metalloproteinases (MMPs) and migration and invasion of cancer cells in prostate cancer. Here we investigated whether the down-regulation of SFMBT2 regulates the infiltration of preadipocytes and tumor-associated macrophages (TAMs) in prostate cancer. We found that the down-regulation of SFMBT2 promotes the infiltration of preadipocytes and TAMs through up-regulation of CXCL8, CCL2, CXCL10, and CCL20 expression in prostate cancer. Expression of CXCL8, CCL2, CXCL10, and CCL20 was also elevated in prostate cancer patients having a higher Gleason score (≥8), which had substantially lower SFMBT2 expression. We also found that the up-regulation of CXCL8, CCL2, CXCL10, and CCL20 expression is dependent on NF-κB activation in prostate cancer cells expressing a low level of SFMBT2. Moreover, increased IL-6 from infiltrated preadipocytes and TAMs promoted migration and invasion of prostate cancer cells expressing a low level of SFMBT2. Our study may suggest that SFMBT2 a critical regulator for the infiltration of preadipocytes and TAMs into the prostate tumor microenvironment. Thus, the regulation of SFMBT2 may provide a new therapeutic strategy to inhibit prostate cancer metastasis, and SFMBT2 could be used as a potential biomarker in prostate cancer metastasis.

Evaluation of Gleason Grade Group 5 in a Contemporary Prostate Cancer Grading System and Literature Review

INTRODUCTION

The aim of this study was to validate contemporary grading systems, in particular, the Gleason grade group (GGG) 5.

PATIENTS AND METHODS

We retrospectively reviewed the clinicopathologic data of 176 patients who underwent radical prostatectomy and whose pathologic results were GGG 4 or 5. The endpoints were biochemical recurrence (BCR) and castration-resistant prostate cancer (CRPC).

RESULTS

The GGG 4 group was composed of 69 patients. The GGG 5 group consisted of 78 patients with GS 4+5 and 29 patients with GS 5+4 or higher. The 5-year BCR-free survival rates for men with GGG 4, GS 4+5, and GS 5+4 or higher were 59%, 54%, and 20%, respectively, and the 5-year CRPC-free survival rates were 98%, 100%, and 88%, respectively. Both the BCR- and CRPC-free survival rates were significantly higher in GS 4+5 than in GS 5+4 or higher (P < .001 and P = .002, respectively), but there were no significant differences between GGG 4 and GS 4+5 (P = .702 and P = .803, respectively). The multivariate analysis demonstrated that GS 5+4 or higher (hazard ratio, 3.4; P = .002) and lymphovascular invasion (hazard ratio, 3.4; P < .001) greatly affected BCR.

CONCLUSION

Our follow-up study revealed that men with GS 4+5 and those with GGG 4 had a similar prognosis. However, there was a significant discrepancy in prognosis between GS 4+5 and GS 5+4 or higher. This suggested that GGG 4 and 5 in the contemporary prostate cancer grading system should be reviewed. Furthermore, lymphovascular invasion may be useful to subgroup these pathologically high-risk patients.

Age-specific survival in prostate cancer using machine learning

Purpose

The incidence of prostate cancer is increasing from the past few decades. Various studies have tried to determine the survival of patients, but metastatic prostate cancer is still not extensively explored. The survival rate of metastatic prostate cancer is very less compared to the earlier stages. The study aims to investigate the survivability of metastatic prostate cancer based on the age group to which a patient belongs, and the difference between the significance of the attributes for different age groups.

Design/methodology/approach

Data of metastatic prostate cancer patients was collected from a cancer hospital in India. Two predictive models were built for the analysis-one for the complete dataset, and the other for separate age groups. Machine learning was applied to both the models and their accuracies were compared for the analysis. Also, information gain for each model has been evaluated to determine the significant predictors for each age group.

Findings

The ensemble approach gave the best results of 81.4% for the complete dataset, and thus was used for the age-specific models. The results concluded that the age-specific model had the direct average accuracy of 83.74% and weighted average accuracy of 79.9%, with the highest accuracy levels for age less than 60.

Originality/value

The study developed a model that predicts the survival of metastatic prostate cancer based on age. The study will be able to assist the clinicians in determining the best course of treatment for each patient based on ECOG, age and comorbidities.

Sites of synchronous distant metastases and prognosis in prostate cancer patients with bone metastases at initial diagnosis: a population-based study of 16,643 patients

BACKGROUND

Bone is a preferential site for prostate cancer (PCa) metastasis. However, sites of synchronous distant metastases in PCa patients with bone metastases at initial diagnosis and their impacts on prognosis are still unclear, limiting our ability to better stratify and treat the patients. In this study, we examined the sites of synchronous extra-skeletal metastases in de novo PCa patients with bone metastases and their associated prognoses.

METHODS

In total, 16,643 de novo PCa patients with bone metastases from the SEER database were included. After stratification of metastatic sites (bone, lung, liver, and brain) and treatment modalities, overall survival (OS) and independent predictors of OS, were analyzed.

RESULTS

Lung was the most frequent site of synchronous metastases, followed by liver, while brain metastases were relatively uncommon. Patients with bone-only metastases showed the longest mean survival time (35.87 months, p < 0.001), followed by patients with bone and lung metastases (30.74 months, p < 0.001). Patients with bone and liver metastases had the shortest mean survival time (17.39 months, p < 0.001). Age > 70 years, unmarried status, high tumor grade, prostate-specific antigen (PSA) > 50 ng/ml, and Gleason score ≥ 8 were associated with poor OS (all p < 0.01). Asian or Pacific Islander ethnic background was associated with a favorable OS (all p < 0.01). Chemotherapy improved OS in patients without brain metastases (all p < 0.05). For patients with bone-only metastases, radical prostatectomy (RP) (HR, 0.339; 95% CI 0.231-0.495; p < 0.001), brachytherapy (BT) (HR, 0.567; 95% CI 0.388-0.829; p = 0.003), and chemotherapy (HR, 0.850; 95% CI 0.781-0.924; p < 0.001) were associated with prolonged OS.

CONCLUSIONS

Age, race, tumor grade, PSA, Gleason score, sites of synchronous extra-skeletal metastases, as well as treatment modalities affected OS in newly diagnosed PCa patients with bone metastases. Synchronous liver metastases were associated with poor OS. Chemotherapy improved OS in patients without brain metastases. RP and BT improved OS in patients with bone-only metastases. Further investigation is warranted to validate these findings.

Gleason pattern 5 is associated with an increased risk for metastasis following androgen deprivation therapy and radiation: An analysis of RTOG 9202 and 9902

BACKGROUND/PURPOSE

Stratification of Gleason score (GS) into three categories (2-6, 7, and 8-10) may not fully utilize its prognostic discrimination, with Gleason pattern 5 (GP5) previously identified as an independent adverse factor.

MATERIALS/METHODS

Patients treated on RTOG 9202 (n = 1292) or RTOG 9902 (n = 378) were pooled and assessed for association of GS and GP5 on biochemical failure (BF), local failure (LF), distant metastasis (DM), and overall survival (OS). Fine and Gray's regression and cumulative incidence methods were used for univariate and multivariate analyses.

RESULTS

With median follow-up of 9.4 years, patients with GS 8-10 with GP5 had worse outcome than GS 4 + 4 for DM on both RTOG9202 (p = 0.038) and RTOG9902 (p < 0.001) with a trend toward worse OS (p = 0.059 and p = 0.089, respectively), but without differences in BF or LF. At 10-years DM was higher by 11% (RTOG 9202) and 18% (RTOG 9902) with GP5 compared to GS 4 + 4. On multivariate analysis restricted to long-term androgen deprivation therapy the presence of GP5 substantially increased distant metastasis (HR = 0.43, 95%CI: 0.24-0.76, p = 0.0039) with a trend toward worse OS (HR:0.74, 95% CI:0.54-1.0, p = 0.052) without association with LF (HR:0.55, 95%CI:0.28-1.09, p = 0.085) or BF (HR:1.15, 95%CI:0.84-1.59, p = 0.39). We did not observed substantial differences between Gleason 3 + 5, 5 + 3, or Gleason 9-10.

CONCLUSIONS

These results validate GP5 as an independent prognostic factor which is strongest for DM. As a result GP5 should be considered when stratifying patients with GS 8 and may be a patient population in which to evaluate newly approved systemic therapies or additional local treatments.

Development and validation of prognostic nomograms for patients with metastatic prostate cancer

OBJECTIVE

This study aimed to develop and validate nomograms to predict overall survival (OS) and cancer-specific survival (CSS) in patients with prostate cancer.

METHODS

Clinical data of patients with mPCa between 2010 and 2014 were retrieved retrospectively, and randomized into training (2/3) and validation sets (1/3). Nomograms were built with potential risk factors based on COX regression analysis. Accuracy was validated using the discrimination and calibration curve for the training and validation groups, respectively.

RESULTS

6659 mPCa patients were collected and enrolled, including 4440 in the training set and 2219 in the validation set. Multivariate analysis showed that age, marital status, PSA, biopsy Gleason score, T stage, and bone metastasis were independent risk factors for both OS and CSS. The concordance index (C-index) of OS was 0.735 (95% CI 0.722-0.748) for the internal validation and 0.735 (95% CI 0.717-0.753) for the external validation. For CSS, it was 0.734 (95% CI 0.721-0.747) and 0.742 (95% CI 0.723-0.761), respectively. The nomograms for predicting OS and CSS displayed better discrimination power in both training and validation sets. Moreover, a favorable consistency between the predicted and actual survival probabilities was demonstrated using calibration curves.

CONCLUSIONS

The nomograms showed good performances for predicting OS and CSS in patients with prostate cancer. It might be a convenient individualized predictive tool for prognosis in clinical practice.

Prognostic Significance of Young Age and Non-Bone Metastasis at Diagnosis in Patients with Metastatic Prostate Cancer: a SEER Population-Based Data Analysis

Objective: This study compared the clinicopathological features and survival of metastatic prostate cancer (mPCa) after stratification by age and non-bone-related metastasis to identify prognostic factors.

Methods: Patients with mPCa between 2010 and 2015 were identified from the Surveillance, Epidemiology and End Results database and analyzed. The overall survival (OS) rate was assessed using the Kaplan-Meier curve and log-rank test as well as multivariate Cox regression analysis.

Results: Among the 10147 patients with mPCa, 5378 were classified as young (≤70 years), 3140 were classified as middle-aged (70-82 years), and 1629 were classified as elderly (> 82 years). The younger patients with a single site metastasis with non-regional lymph nodes (NRLN) had a better prognosis than those with bone metastasis [hazard ratio (HR), 0.59, 95% confidence interval (CI), 0.47-0.73, P < 0.001], whereas patients with liver metastasis had the worst OS rate (P = 0.001). Moreover, patients in the middle-aged group with NRLN or lung metastasis had a better prognosis than those with bone metastasis (P < 0.05). The OS rate of patient with bone + liver and bone + brain metastasis was poorer (P < 0.001) than those with bone + NRLN metastasis in the younger patients (P < 0.05). The elder patients with bone + lung metastasis had the worst OS (HR, 1.54; 95% CI, 1.25-1.90, P < 0.001), although the death risk of patients with bone + brain and bone + NRLN metastasis not significantly different (P > 0.05). However, the OS of the patients with bone + liver metastasis remained the worst (P < 0.001).

Conclusions: Prostate cancer patients with lung metastasis or younger patients (≤70 years old) with bone + lung metastases had better OS than patients with other types of metastasis or old age.

TRPM4 channel is involved in regulating epithelial to mesenchymal transition, migration, and invasion of prostate cancer cell lines

Transient Receptor Potential Melastatin 4 (TRPM4) is a Ca²⁺ -activated and voltage-dependent monovalent cation channel, which depolarizes the plasma cell membrane, thereby modulating Ca²⁺ influx across Ca²⁺ -permeable pathways. TRPM4 is involved in different physiological processes such as T cell activation and the migration of endothelial and certain immune cells. Overexpression of this channel has been reported in various types of tumors including prostate cancer. In this study, a significant overexpression of TRPM4 was found only in samples from cancer with a Gleason score higher than 7, which are more likely to spread. To evaluate whether TRPM4 overexpression was related to the spreading capability of tumors, TRPM4 was knockdown by using shRNAs in PC3 prostate cancer cells and the effect on cellular migration and invasion was analyzed. PC3 cells with reduced levels of TRPM4 (shTRPM4) display a decrease of the migration/invasion capability. A reduction in the expression of Snail1, a canonical epithelial to mesenchymal transition (EMT) transcription factor, was also observed. Consistently, these cells showed a significant change in the expression of key EMT markers such as MMP9, E-cadherin/N-cadherin, and vimentin, indicating a partial reversion of the EMT process. Whereas, the overexpression of TRPM4 in LnCaP cells resulted in increased levels of Snail1, reduction in the expression of E-cadherin and increase in their migration potential. This study suggests a new and indirect mechanism of regulation of migration/invasion process by TRPM4 in prostate cancer cells, by inducing the expression of Snail1 gene and consequently, increasing the EMT.

Reduced Arginyltransferase 1 is a driver and a potential prognostic indicator of prostate cancer metastasis

Most prostate cancer cases remain indolent for long periods of time, but metastatic progression quickly worsens the prognosis and leads to mortality. However, little is known about what promotes the metastasis of prostate cancer and there is a lack of effective prognostic indicators, making it immensely difficult to manage options for treatment or surveillance. Arginyltransferase 1 (Ate1) is the enzyme mediating post-translational protein arginylation, which has recently been identified as a master regulator affecting many cancer-relevant pathways including stress response, cell cycle checkpoints, and cell migration/adhesion. However, the precise role of Ate1 in cancer remains unknown. In this study, we found the occurrence of metastasis of prostate cancer is inversely correlated with the levels of Ate1 protein and mRNA in the primary tumor. We also found that metastatic prostate cancer cell lines have a reduced level of Ate1 protein compared to non-metastatic cell lines, and that a depletion of Ate1 drives prostate cancer cells towards more aggressive pro-metastatic phenotypes without affecting proliferation rates. Furthermore, we demonstrated that a reduction of Ate1 can result from chronic stress, and that shRNA-reduced Ate1 increases cellular resistance to stress, and drives spontaneous and stress-induced genomic mutations. Finally, by using a prostate orthotropic xenograft mouse model, we found that a reduction of Ate1 was sufficient to enhance the metastatic phenotypes of prostate cancer cell line PC-3 in vivo. Our study revealed a novel role of Ate1 in suppressing prostate cancer metastasis, which has a profound significance for establishing metastatic indicators for prostate cancer, and for finding potential treatments to prevent its metastasis.

De novo metastatic castration sensitive prostate cancer: State of art and future perspectives

De novo metastatic castration sensitive prostate cancer (mCSPC) accounts for about 4% of all prostate tumors in Western Countries. This condition has a heterogeneous biological e clinical behavior, ranging from indolent to aggressive and rapidly fatal forms. Recently, the therapeutic landscape for mCSPC has been broadly enriched; indeed robust evidence supports the addiction of chemotherapy (docetaxel) or abiraterone acetate to androgen deprivation therapy (ADT), the latter considered for long the unique standard of care. However, the prognostic stratification and the definition of the ideal therapeutic approach for the subpopulation of de novo mCSPC - albeit largely represented in pivotal clinical trials enrolling mCSPC patients - have yet to be prospectively outlined. The aim of this review was to describe the current state of art about clinical presentation, prognostic classification, and different therapeutic options available for de novo mCSPC patients. Furthermore, we shed light on ongoing clinical trials and future perspectives for this disease setting.

The relationship between diabetes, prostate-specific antigen screening tests, and prostate cancer

PURPOSE

Men with diabetes have been found to have a reduced risk of prostate cancer (PCa), potentially due to detection bias from lower prostate-specific antigen (PSA) levels or inhibition of tumor growth. Understanding if lower PCa rates are due to a lower risk of the disease or a detection bias from PSA testing can help inform the benefits and harms from prostate cancer screening.

METHODS

We used data from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Screening Trial to assess the impact of PSA screening on PCa in men with diabetes and the potential role of detection bias and/or slower tumor growth. Comparing men by diabetes status, we calculated age-adjusted incidence rates by tumor grade and compared screening results, PSA levels, and tumor characteristics.

RESULTS

Men with diabetes had lower rates of PCa but was limited to low- and intermediate-grade tumors. Men with diabetes were less likely to be biopsied after their first positive screening test and men diagnosed with low/intermediate-grade tumors had significantly more advanced tumors with higher PSA levels.

CONCLUSIONS

Our findings provide additional evidence that detection bias is likely contributing to the lower rates of low- and intermediate-grade prostate cancers.

SFMBT2 (Scm-like with four mbt domains 2) negatively regulates cell migration and invasion in prostate cancer cells

Metastatic prostate cancer is the leading cause of morbidity and mortality in men. In this study, we found that expression level of SFMBT2 is altered during prostate cancer progression and has been associated with the migration and invasion of prostate cancer cells. The expression level of SFMBT2 is high in poorly metastatic prostate cancer cells compared to highly metastatic prostate cancer cells. We also found that SFMBT2 knockdown elevates MMP-2, MMP-3, MMP-9, and MMP-26 expression, leading to increased cell migration and invasion in LNCaP and VCaP cells. SFMBT2 interacts with YY1, RNF2, N-CoR and HDAC1/3, as well as repressive histone marks such as H3K9me2, H4K20me2, and H2AK119Ub which are associated with transcriptional repression. In addition, SFMBT2 knockdown decreased KAI1 gene expression through up-regulation of N-CoR gene expression. Expression of SFMBT2 in prostate cancer was strongly associated with clinicopathological features. Patients having higher Gleason score (≥ 8) had substantially lower SFMBT2 expression than patients with lower Gleason score. Moreover, tail vein or intraprostatic injection of SFMBT2 knockdown LNCaP cells induced metastasis. Taken together, our findings suggest that regulation of SFMBT2 may provide a new therapeutic strategy to control prostate cancer metastasis as well as being a potential biomarker of metastatic prostate cancer.

MicroRNA-211 suppresses prostate cancer proliferation by targeting SPARC

Dysregulation of microRNAs (miRNAs/miRs) is frequently associated with cancer progression. Altered expression of miR-211 has been observed in various types of human cancer; however, its expression and role in prostate cancer (PCa) remains unknown. In the present study, the expression of miR-211 in PCa cell lines and tissues was measured by reverse transcription-quantitative PCR (qPCR), revealing that miR-211 was downregulated in PCa cell lines and tissues. Further analysis revealed that low miR-211 was associated with the tumor stage and Gleason score. With the assistance of miR-211 mimics and inhibitor, it was also revealed that the overexpression of miR-211 could inhibit PCa cell proliferation in vitro. Conversely, downregulated miR-211 expression promotes PCa cell proliferation. In addition, the secreted protein acidic and rich in cysteine (SPARC) was identified as a target of miR-211 in the PCa cell lines, and SPARC expression was inversely associated with miR-211. In conclusion, it was demonstrated that the miR-211 expression was downregulated in PCa cell lines and tissues. Additionally, miR-211 could inhibit PCa cell proliferation partially by downregulating SPARC. Therefore, miR-211 may be a potential therapeutic target for PCa treatment in the future.

Incidence of metastasis and prostate-specific antigen levels at diagnosis in Gleason 3+4 versus 4+3 prostate cancer

Aims:

The aim is to assess for a difference in the incidence of metastasis (IM) and prostate-specific antigen (PSA) levels at diagnosis in patients with Gleason score (GS) 3+4 versus 4+3 prostate cancer using a large veterans affairs database.

Subjects and Methods:

A retrospective review of 1402 medical records from 5 VA hospitals was conducted. The study period was from 2009 to 2014. Primary endpoints were IM and PSA levels at diagnosis. A secondary endpoint was overall survival.

Statistical Analysis Used:

Chi-square tests for categorical variables, Student's t-test for continuous, normally distributed variables, and rank sum tests for continuous nonnormally distributed variables.

Results:

There were 1050 patients with GS3+4 and 352 with GS4+3. There were no differences in sociodemographic and clinical characteristics of the study population. PSA at the time of diagnosis was significantly higher in the GS4+3 patients compared to GS3+4 (18.0 vs. 11.4, respectively; P < 0.001). The IM at diagnosis was higher in the GS4+3 patients (10/352) compared to GS3+4 (9/1041) (2.8% vs. 0.9%; P = 0.005). In an adjusted model, GS4+3 was associated with higher PSA, higher IM at diagnosis. There was no difference in overall survival between the 2 groups though a 23% reduction in overall survival in the GS4+3 was noted (P = 0.53).

Conclusions:

Our results indicate that patients with GS4+3 prostate cancers have higher PSA levels at diagnosis. GS4+3 is associated with 3-fold increased risk of IM at diagnosis than GS3+4 though the overall incidence is low. Further research is needed to assess whether GS4+3 patients need routine staging imaging investigations at the time of diagnosis similar to patients with higher Gleason scores (GS ≥8).

Assessment of the prognostic value of the 8th AJCC staging system for patients with clinically staged prostate cancer; A time to sub-classify stage IV?

BACKGROUND

The American Joint Committee on Cancer (AJCC) staging system (8th edition) for prostate cancer has been published. The current study seeks to validate the prognostic performance of the changes in the new system among clinically staged prostate cancer patients registered within the surveillance, epidemiology and end results (SEER) database.

METHODS

SEER database (2004-2014) has been accessed through SEER*Stat program and AJCC 7th and 8th edition stages were calculated utilizing T, N and M stages as well as baseline prostatic specific antigen (PSA) and grade group. Cancer-specific and overall survival analyses according to 6th, 7th and 8th editions were conducted through Kaplan-Meier analysis. Moreover, multivariate analysis was conducted through a Cox proportional hazard model.

RESULTS

A total of 110499 patients with prostate cancer were identified in the period from 2004-2014.For cancer- specific survival according to 8th AJCC, all pair wise P values for comparison were significant (<0.01) except for stage IIA vs. IIB; while for overall survival according to 8th AJCC, all pair wise P values for comparison were significant (<0.02) except for stage IIIA vs. IIIB. Results of c-index assessment for cancer-specific survival for the three AJCC editions were as follows: c-index for AJCC 6th edition was 0.816; c-index for AJCC 7th edition was 0.897; c-index for AJCC 8th edition was 0.907. For stage IVB prostate cancer (i.e.M1 disease), further sub-staging was proposed according to M1 sub-stage (i.e. M1a, M1b and M1c). Pair wise comparison between these proposed sub-stages was conducted for both cancer-specific and overall survival. For both cancer-specific and overall survival, all pair wise P values for comparisons were <0.0001.

CONCLUSION

Compared to older staging systems (6th and 7th), the 8th system is more discriminatory. Further sub-classification of stage IV disease is suggested.

Validation of American Joint Committee on Cancer eighth staging system among prostate cancer patients treated with radical prostatectomy

Background

The objective in this paper was to validate the prognostic performance of the American Joint Committee on Cancer (AJCC) 7th and 8th systems among prostate cancer patients treated with radical prostatectomy.

Methods

The surveillance, epidemiology and end results (SEER) database (2006-2014) was accessed through the SEER*Stat program and AJCC 7th and 8th editions were calculated utilizing T, N and M stages, histological grade group, as well as baseline prostatic-specific antigen (PSA). Cancer-specific and overall survival analyses according to 7th and 8th editions were conducted. Moreover, multivariate analysis was conducted through a Cox proportional hazard model.

Results

A total of 72,999 patients with prostate cancer were identified in the period from 2006 to 2014. Overall survival was assessed according to AJCC 7th and 8th staging systems. The test for trend for overall survival was significant (p < 0.0001) for both staging systems. Concordance index for AJCC 7th system was: 0.791 [standard error of the mean (SE): 0.017; 95% CI: 0.758-0.825]; while concordance index for AJCC 8th system was: 0.840 (SE: 0.015; 95% CI: 0.811-0.869). In a multivariate analysis among patients with M0 disease, lower grade group, N0 stage and pT2 stage were associated with better cancer-specific survival (p < 0.01); while PSA level did not predict cancer-specific survival.

Conclusion

There is a clear improvement in the discriminatory ability for AJCC 8th versus AJCC 7th staging system in the postprostatectomy setting. This may be related to better integration of biological factors into the staging system.

Low TIM3 expression indicates poor prognosis of metastatic prostate cancer and acts as an independent predictor of castration resistant status

T cell immunoglobulin 3 (TIM3) is a cell surface star molecule expressed on T cells, and also marks dysfunctional CD8⁺ T cells in various kinds of cancers. However, there are few studies focusing on the expression of TIM3 in tumor cells. In our study, we recruited 139 patients with metastatic prostate cancer (mPCa) who received transurethral resection of the prostate (TURP) consecutively to examine whether TIM3 expression level is associated with overall survival (OS) in mPCa patients. Immunohistochemistry was performed to determine TIM3 expression in prostate cancer tissues and then patients were divided into two groups. In multivariate Cox analysis, we revealed that mPCa patients with negative TIM3 expression, younger age, no radiotherapy, higher Gleason score, higher cT stage and patients of mCRPC had a shorter OS. Therefore, a predictive nomogram was generated with identified independent prognostic factors to assess patients’ OS at 3 years. Multivariate logistic regression revealed that higher cT stage, higher Gleason score and low TIM3 expression were independent predictors of metastatic castration resistant prostate cancer (mCRPC). In conclusion, low expression level of TIM3 in prostate cancer tissues is an independent prognostic factor of poor prognosis for mPCa patients, and also an independent predictor of mCRPC.

Predictive efficacy of the 2014 International Society of Urological Pathology Gleason grading system in initially diagnosed metastatic prostate cancer

We compared the predictive ability of the 2014 and 2005 Gleason grading systems in 568 patients initially diagnosed with metastatic prostate cancer (PCa). Outcomes included the duration of castration-resistant prostate cancer-free survival (CFS) and overall survival (OS). Univariate analyses and log-rank tests were used to identify prognosis indicators and assess univariable differences in CFS and OS in Gleason score (GS) groups. Cox proportional hazards and area under the curves of receiver operator characteristics methods were used to evaluate the predictive efficacy of the 2005 and 2014 ISUP grading systems. Univariate analyses showed that the 2005 and 2014 grading systems were prognosticators for CFS and OS; both systems could distinguish the clinical outcome of patients with GS 6, GS 7, and GS 8–10. Using the 2014 criteria, no statistical differences in patient survival were observed between GS 3 + 4 and GS 4 + 3 or GS 8 and GS 9–10. The predictive ability of the 2014 and 2005 grading systems was comparable for CFS and OS (P = 0.321). However, the 2014 grading system did not exhibit superior predictive efficacy in patients initially diagnosed with PCa and bone metastasis; trials using larger cohorts are required to confirm its predictive value. To the best of our knowledge, ours is the first study to compare the 2005 and 2014 grading systems in initially diagnosed PCa with bone metastasis. At present, we recommend that both systems should be used to predict the prognosis of patients with metastatic PCa.

Outcome of Gleason 3 + 5 = 8 Prostate Cancer Diagnosed on Needle Biopsy: Prognostic Comparison with Gleason 4 + 4 = 8

PURPOSE

ISUP (International Society for Urologic Pathology) and WHO adopted prognostic Grade Groups 1 to 5 that simplify prostate cancer grading for prognosis. Grade Group 4 is Gleason score 8 cancer, which is heterogeneous, and it encompasses Gleason score 4 + 4 = 8, 3 + 5 = 8 and 5 + 3 = 8. The comparative prognostic implications of these various Gleason scores had not been studied by urological pathologists after a re-review of slides.

MATERIALS AND METHODS

Patients with a highest biopsy Gleason score of 3 + 5 = 8 or 4 + 4 = 8 were included in the study. Controls were cases with a highest Gleason score of 4 + 3 = 7 or 9-10. A total of 423 prostatic biopsy cases accessioned from 2005 to 2013 at 2 institutions were reviewed. Clinicopathological findings and followup (median 33.4 months) were assessed.

RESULTS

Among Gleason score 8 cancers the cancer status outcome in 51 men with Gleason score 3 + 5 = 8 was marginally worse than in 114 with Gleason score 4 + 4 = 8 (p = 0.04). This was driven by a persistent nonmetastatic (after radiation/hormone therapy) cancer rate of 37% among Gleason score 3 + 5 = 8 cases vs 24% among Gleason score 4 + 4 = 8 cases. Conversely, cancer specific survival at 36-month followup was 97.8% in 3 + 5 cases vs 92.6% in 4 + 4 cases but this was not significant (p = 0.089). Cancer specific survival in the Gleason score 8 group was dichotomized by the presence of cribriform growth (p = 0.018). All Gleason score categories did not differ in the fraction of biopsy cores positive, clinical presentation or pathological findings, including the frequency of Gleason pattern 5, in 70 patients who underwent prostatectomy.

CONCLUSIONS

Using the most current standards of prostate cancer grading the prognosis is not different in Gleason score 3 + 5 = 8 and 4 + 4 = 8 cancers. This justifies including both in Grade Group 4.

12-HETER1/GPR31, a high-affinity 12(S)-hydroxyeicosatetraenoic acid receptor, is significantly up-regulated in prostate cancer and plays a critical role in prostate cancer progression

Previously we identified and deorphaned G-protein-coupled receptor 31 (GPR31) as the high-affinity 12(S)-hydroxyeicosatetraenoic acid [12(S)-HETE] receptor (12-HETER1). Here we have determined its distribution in prostate cancer tissue and its role in prostate tumorigenesis using in vitro and in vivo assays. Data-mining studies strongly suggest that 12-HETER1 expression positively correlates with the aggressiveness and progression of prostate tumors. This was corroborated with real-time PCR analysis of human prostate tumor tissue arrays that revealed the expression of 12-HETER1 positively correlates with the clinical stages of prostate cancers and Gleason scores. Immunohistochemistry analysis also proved that the expression of 12-HETER1 is positively correlated with the grades of prostate cancer. Knockdown of 12-HETER1 in prostate cancer cells markedly reduced colony formation and inhibited tumor growth in animals. To discover the regulatory factors, 5 candidate 12-HETER1 promoter cis elements were assayed as luciferase reporter fusions in Chinese hamster ovary (CHO) cells, where the putative cis element required for gene regulation was mapped 2 kb upstream of the 12-HETER1 transcriptional start site. The data implicate 12-HETER1 in a critical new role in the regulation of prostate cancer progression and offer a novel alternative target for therapeutic intervention.-Honn, K. V., Guo, Y., Cai, Y., Lee, M.-J., Dyson, G., Zhang, W., Tucker, S. C. 12-HETER1/GPR31, a high-affinity 12(S)-hydroxyeicosatetraenoic acid receptor, is significantly up-regulated in prostate cancer and plays a critical role in prostate cancer progression.

Stereotactic body radiotherapy in oligometastatic prostate cancer patients with isolated lymph nodes involvement: a two-institution experience

OBJECTIVE

Stereotactic body radiotherapy (SBRT) is emerging as a treatment option in oligometastatic cancer patients. This retrospective study aimed to analyze local control, biochemical progression-free survival (b-PFS), and toxicity in patients affected by isolated prostate cancer lymph node metastases. Finally, we evaluated androgen deprivation therapy-free survival (ADT-FS).

METHODS

Forty patients with 47 isolated lymph nodes of recurrent prostate cancer were treated with SBRT. Mostly, two different fractionation schemes were used: 5 × 7 Gy in 23 (48.9 %) lesions and 5 × 8 Gy in 13 (27.7 %) lesions. Response to treatment was assessed with periodical PSA evaluation. Toxicity was registered according to RTOG/EORTC criteria.

RESULTS

With a mean follow-up of 30.18 months, local control was achieved in 98 % of the cases, with a median b-PFS of 24 months. We obtained a 2-year b-PFS of 44 % with 40 % of the patients ADT-free at last follow-up (mean value 26.18 months; range 3.96-59.46), whereas 12.5 % had a mean ADT-FS of 13.58 months (range 2.06-37.13). Late toxicity was observed in one (2.5 %) patient who manifested a grade 3 gastrointestinal toxicity 11.76 months after the end of SBRT.

CONCLUSION

Our study demonstrates that SBRT is safe, effective, and minimally invasive in the eradication of limited nodal metastases, yielding an important delay in prescribing ADT.

SBRT: An Opportunity to Improve Quality of Life for Oligometastatic Prostate Cancer

Objective

Oligometastatic prostate cancer is a limited metastatic disease state in which potential long-term control is still possible with the use of targeted therapies such as surgery or stereotactic body radiation therapy (SBRT). SBRT may as well potentially prolong the time before the initiation of androgen deprivation therapy (ADT) and docetaxel chemotherapy for oligometastatic prostate cancer. The goal of this study is to outline prognostic factors associated with improved outcome with SBRT for metastatic prostate cancer and to quantify the effect of prior systemic treatments such as ADT and docetaxel on survival after SBRT.

Methods

Twenty-four prostate cancer patients were treated with SBRT at the Philadelphia CyberKnife Center between August 2007 and April 2014. Retrospective data collection and analysis were performed for these patients on this Institutional Review Board approved study. Kaplan–Meier methodology was utilized to estimate and visually assess overall survival (OS) at the patient level, with comparisons accomplished using the log-rank test. Unadjusted hazard ratios were estimated using Cox proportional hazards regression modeling.

Results

An improved median survival was noted for patients with oligometastatic disease defined as ≤4 lesions with median survival of >3 years compared with 11 months for polymetastases (p = 0.02). The use of docetaxel at some time in follow-up either before or after SBRT was associated with decreased survival with median survival of 9 months vs. >3 years (p = 0.01).

Conclusion

Prognosis was better for men with recurrent prostate cancer treated with SBRT if they had ≤4 metastases (oligometastases) or if docetaxel was not necessary for salvage treatment. The prolonged median OS for men with oligometastases in this population of heavily pretreated prostate cancer patients following SBRT may allow for improved quality of life because of a delay of more toxic salvage therapies.

Serum C-reactive protein acted as a prognostic biomarker for overall survival in metastatic prostate cancer patients

The aim of this study was to determine whether baseline serum C-reactive protein (CRP) levels were associated with overall survival in patients with metastatic prostate cancer in the Chinese population. A total of 135 patients with metastatic prostate cancer were retrospectively reviewed. Both Kaplan-Meier product-limit method and multivariable analysis by Cox regression model were used to assess the prognostic role of serum CRP levels on overall survival of patients with metastatic prostate cancer. There were 51 patients (37.8%) with higher values of baseline serum CRP levels (≥10 mg/L). Kaplan-Meier product-limit method and log-rank test showed that patients with high serum CRP level (≥10 mg/L) had significantly worse overall survival than those patients with normal serum CRP level (<10 mg/L) (P < 0.001). The multivariable analysis by Cox regression model further showed that high serum CRP level (≥10 mg/L) was a significantly independent predictor of overall survival (hazard ratio (HR) = 2.39; 95% confidence interval (95% CI) 1.56-2.39, P < 0.001). In addition, high Gleason score (≥8) also was an independent predictor of overall survival (HR = 1.80; 95% CI 1.16-2.79, P = 0.008). In conclusion, serum CRP level is useful to predict the prognosis of metastatic prostate cancer patients, and high serum CRP level is a significantly independent predictor of worse overall survival.