Biomarkers in localized prostate cancer

CRISPR-Cas-based biosensors for the detection of cancer biomarkers

Along with discovering cancer biomarkers, non-invasive detection methods have played a critical role in early cancer diagnosis and prognostic improvement. Some traditional detection methods have been used for detecting cancer biomarkers, but they are time-consuming and involve materials and human costs. With great flexibility, sensitivity and specificity, the clustered regularly interspaced short palindromic repeats (CRISPR)-associated system provides a wide range of application prospects in this field. Herein, we introduce the background of the CRISPR-Cas (CRISPR-associated) system and comprehensively summarize the diagnosis strategies of cancer mediated by the CRISPR-Cas system, including four kinds of biochemical-based markers: nucleic acid, enzyme, tumor-specific protein and exosome. Furthermore, we discuss the challenges in implementing the CRISPR-Cas system in clinical applications.

Clinical and Radiological Factors for Predicting Clinically Significant Prostate Cancer in Biopsy-Naive Patients With PI-RADS 3 Lesions

OBJECTIVE

This study intends to examine the anticipatory power of clinical and radiological parameters in detecting clinically significant prostate cancer in patients demonstrating Prostate Imaging Reporting and Data System 3 lesions.

METHODS

This was a retrospective study. The study included participation from 453 patients at the First Affiliated Hospital of Soochow University, sampled between September 2017 through August 2022. Each patient underwent a routine 12-core prostate biopsy followed by a 2 to 5 core fusion-targeted biopsy. We utilized both univariate and multivariate logistic regression analyses to identify the parameters that have a correlation with clinically significant prostate cancer. The predictive ability of these parameters was assessed using the receiver operating characteristic curve, leading to the creation of a nomogram.

RESULTS

Clinically significant prostate cancer was detected in 68 out of 453 patients with Prostate Imaging Reporting and Data System 3 lesions (15.01%). Among Prostate Imaging Reporting and Data System 3a and 3b patients, 4.78% (3.09% of the total) and 33.75% (11.92% of the total), respectively, had clinically significant prostate cancer. Systematic biopsy improved prostate cancer and clinically significant prostate cancer detection rates by 7.72% and 3.09%, respectively, compared to targeted biopsy. Without systematic biopsy, there would be an undetected rate of 15% for prostate cancer and 8.13% for clinically significant prostate cancer in Prostate Imaging Reporting and Data System 3b patients. Several clinical parameters, including age, prostate-specific antigen density, lesion volume, apparent diffusion coefficient, and digital rectal examination, were statistically significant in the logistic regression analysis for clinically significant prostate cancer. The individual diagnostic accuracies of these parameters for clinically significant prostate cancer were 0.648, 0.645, 0.75, 0.763, and 0.7, respectively, but their combined accuracy improved to 0.866. A well-fit nomogram based on the identified risk factors was constructed (χ2 = 10.254, P = .248).

CONCLUSION

The combination of age, prostate-specific antigen density, lesion volume, apparent diffusion coefficient, and digital rectal examination presented a higher diagnostic value for clinically significant prostate cancer than any single parameter in patients with Prostate Imaging Reporting and Data System 3 lesions. Systematic biopsy proved crucial for biopsy-naive patients with Prostate Imaging Reporting and Data System 3 lesions and should not be omitted.

Decoding the Influence of Obesity on Prostate Cancer and Its Transgenerational Impact

In recent decades, the escalating prevalence of metabolic disorders, notably obesity and being overweight, has emerged as a pressing concern in public health. Projections for the future indicate a continual upward trajectory in obesity rates, primarily attributable to unhealthy dietary patterns and sedentary lifestyles. The ramifications of obesity extend beyond its visible manifestations, intricately weaving a web of hormonal dysregulation, chronic inflammation, and oxidative stress. This nexus of factors holds particular significance in the context of carcinogenesis, notably in the case of prostate cancer (PCa), which is a pervasive malignancy and a leading cause of mortality among men. A compelling hypothesis arises from the perspective of transgenerational inheritance, wherein genetic and epigenetic imprints associated with obesity may wield influence over the development of PCa. This review proposes a comprehensive exploration of the nuanced mechanisms through which obesity disrupts prostate homeostasis and serves as a catalyst for PCa initiation. Additionally, it delves into the intriguing interplay between the transgenerational transmission of both obesity-related traits and the predisposition to PCa. Drawing insights from a spectrum of sources, ranging from in vitro and animal model research to human studies, this review endeavors to discuss the intricate connections between obesity and PCa. However, the landscape remains partially obscured as the current state of knowledge unveils only fragments of the complex mechanisms linking these phenomena. As research advances, unraveling the associated factors and underlying mechanisms promises to unveil novel avenues for understanding and potentially mitigating the nexus between obesity and the development of PCa.

Metabolomics Reveals Novel Serum Metabolic Signatures in Gastric Cancer by a Mass Spectrometry Platform

Gastric cancer (GAS) is one of the malignant tumors of the gastrointestinal system. Alterations in metabolite composition can reflect pathological processes of GAS and constitute a basis for diagnosis and treatment improvements. In this study, a total of 301 serum samples from 150 GAS patients at different tumor-node-metastasis (TNM) stages and 151 healthy controls were collected. Mass spectrometry platforms were performed to investigate the changes in GAS-related metabolites and explore the new potential serum biomarkers and the metabolic dysregulation associated with GAS progression. Twelve differential metabolites (ethyl 2,4-dimethyl-1,3-dioxolane-2-acetate, D-urobilinogen, 14-HDoHE, 13-hydroxy-9-methoxy-10-oxo-11-octadecenoic acid, 5,6-dihydroxyprostaglandin F1a, 9'-carboxy-gamma-tocotrienol, glutaric acid, alanine, tyrosine, C18:2(FFA), adipic acid, and suberic acid) were identified to establish the diagnosis model for GAS. The defined biomarker panel was also statistically significant for GAS progression with different TNM stages. KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment revealed the metabolic dysregulation associated with GAS progression. In conclusion, a diagnostic panel was established and validated, which could be used to further stage the early and advanced GAS patients from healthy controls. These findings may provide useful information for explaining the GAS metabolic alterations and try to facilitate the characterization of GAS patients in the early stage.

microRNA-205 in prostate cancer: Overview to clinical translation

Prostate cancer (PrCa) is the most common type of cancer among men in the United States. The metastatic and advanced PrCa develops drug resistance to current regimens which accounts for the poor management. microRNAs (miRNAs) have been well-documented for their diagnostic, prognostic, and therapeutic roles in various human cancers. Recent literature confirmed that microRNA-205 (miR-205) has been established as one of the tumor suppressors in PrCa. miR-205 regulates number of cellular functions, such as proliferation, invasion, migration/metastasis, and apoptosis. It is also evident that miR-205 can serve as a key biomarker in diagnostic, prognostic, and therapy of PrCa. Therefore, in this review, we will provide an overview of tumor suppressive role of miR-205 in PrCa. This work also outlines miR-205's specific role in targeted mechanisms for chemosensitization and radiosensitization in PrCa. A facile approach of delivery paths for successful clinical translation is documented. Together, all these studies provide a novel insight of miR-205 as an adjuvant agent for reducing the widening gaps in clinical outcome of PrCa patients.

Biosensors for detection of prostate cancer: a review

Diagnosis of prostate cancer (PC) has posed a challenge worldwide due to the sophisticated and costly diagnostics tools, which include DRE, TRUS, GSU, PET/CT scan, MRI, and biopsy. These diagnostic techniques are very helpful in the detection of PCs; however, all the techniques have their serious limitations. Biosensors are easier to fabricate and do not require any cutting-edge technology as required for other imaging techniques. In this regard, point-of-care (POC) biosensors are important due to their portability, convenience, low cost, and fast procedure. This review explains the various existing diagnostic tools for the detection of PCs and the limitation of these methods. It also focuses on the recent studies on biosensors technologies as an alternative to the conventional diagnostic techniques for the detection of PCs.

Rewired Metabolism of Amino Acids and Its Roles in Glioma Pathology

Amino acids (AAs) are indispensable building blocks of diverse bio-macromolecules as well as functional regulators for various metabolic processes. The fact that cancer cells live with a voracious appetite for specific AAs has been widely recognized. Glioma is one of the most lethal malignancies occurring in the central nervous system. The reprogrammed metabolism of AAs benefits glioma proliferation, signal transduction, epigenetic modification, and stress tolerance. Metabolic alteration of specific AAs also contributes to glioma immune escape and chemoresistance. For clinical consideration, fluctuations in the concentrations of AAs observed in specific body fluids provides opportunities to develop new diagnosis and prognosis markers. This review aimed at providing an extra dimension to understanding glioma pathology with respect to the rewired AA metabolism. A deep insight into the relevant fields will help to pave a new way for new therapeutic target identification and valuable biomarker development.

Employing radiography (X-rays) to localize lesions in human skeletal remains from past populations to allow accurate biopsy, using examples of cancer metastases

Clinical research into biomolecules from infectious diseases and cancers has advanced rapidly in recent years, with two key areas being DNA analysis and proteomics. If we wish to understand important diseases and their associated biomolecules in past populations, techniques are required that will allow accurate biopsy of lesions in excavated human skeletal remains. While locating lesions visible on the surface of a bone is simple, many lesions such as cancer metastases are located in the medulla of bones, unseen on visual inspection. Here, we use two novel image guided techniques to investigate how plain radiographs may improve accuracy in the localization of lesions within bones from medieval individuals. While both techniques were effective, we found the grid technique required fewer radiographs than the pointer technique to employ and so was responsible for a lower overall radiation dose. We then discuss methods available for biopsy in archeological bone and how the optimal location for the biopsy of malignant lesions will vary depending upon whether the tumor is blastic or lytic in nature. Limitations of this X-ray guided approach include that not all cancer metastases are visible on plain radiographs, as erosion of cortical bone is frequently required for visualization of lytic metastases using this imaging modality.

The potential diagnostic accuracy of circulating microRNAs for prostate cancer: A meta-analysis

OBJECTIVES

This meta-analysis has been conducted to evaluate the diagnostic accuracy of circulating microRNAs for the early diagnosis of prostate cancer (PCA).

METHODS

A systematic literature search was performed (updated to February 18, 2021) in PubMed, EMBASE, Web of Science, Cochrane Library, Wanfang database and China National Knowledge Infrastructure (CNKI) to identify eligible studies. The pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under curve (AUC) of the summary receiver-operating characteristic (SROC) curve were calculated for both overall and subgroup analysis. The meta-regression and subgroup analysis were performed to explore heterogeneity and Deeks' funnel plot was used to assess publication bias.

RESULTS

One hundred nineteen studies from 33 articles owned 8703 PCA patients and 4914 controls were included in our meta-analysis. The overall sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and area under the curve were 0.79, 0.81, 4.1, 0.26, 16 and 0.87, respectively. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve of miR-21 in diagnosis of PCA were 0.86, 0.90, 8.3, 0.16, 52 and 0.94, respectively. Subgroup analysis suggested that the upregulated miRNA of serum type with large sample size could carry out a better diagnostic accuracy of PCA patients. Moreover, publication bias was not found.

CONCLUSIONS

Circulating microRNA, especially miR-21, can be used as a promising noninvasive biomarker in the early diagnosis of PCA.

Novel Insights into Autophagy and Prostate Cancer: A Comprehensive Review

Autophagy is a complex process involved in several cell activities, including tissue growth, differentiation, metabolic modulation, and cancer development. In prostate cancer, autophagy has a pivotal role in the regulation of apoptosis and disease progression. Several molecular pathways are involved, including PI3K/AKT/mTOR. However, depending on the cellular context, autophagy may play either a detrimental or a protective role in prostate cancer. For this purpose, current evidence has investigated how autophagy interacts within these complex interactions. In this article, we discuss novel findings about autophagic machinery in order to better understand the therapeutic response and the chemotherapy resistance of prostate cancer. Autophagic-modulation drugs have been employed in clinical trials to regulate autophagy, aiming to improve the response to chemotherapy or to anti-cancer treatments. Furthermore, the genetic signature of autophagy has been found to have a potential means to stratify prostate cancer aggressiveness. Unfortunately, stronger evidence is needed to better understand this field, and the application of these findings in clinical practice still remains poorly feasible.

Progress in prostate cancer prevention

After lung, prostate cancer is the second most frequently diagnosed cancer and fourth in cancer-related mortality. The etiology is largely unknown and no clear risk factors have been identified. Primary prevention is therefore challenging. Also, secondary prevention, screening, in large populations is difficult. Germline mutations are implicated in hereditary prostate cancer, accounting for about 10% of screened men. Currently, only prostate-specific antigen test is adopted for early detection but is considered insufficient to further improve prevention and care. In this opinion article, we discuss novel diagnostic biomarkers and imaging tools, along with more promising targeted prostate biopsies.

Predictive value of neutrophil-to-lymphocyte ratio in diagnosis of early prostate cancer among men who underwent robotic transperineal prostate biopsy

To evaluate the predicted value of neutrophil-to-lymphocyte ratio (NLR) in the diagnosis of early prostate cancer by using standardized Full blood count (FBC) performed within 4 weeks before biopsy and histology results from transperineal prostate biopsy (RTPB).Patients who underwent RTPB under general anesthesia (GA), at Urology Department, Singapore General Hospital between September 2006 and Febuary 2016 were retrospectively reviewed.NLR was calculated using full blood count (FBC) that was done as a pre-admission test before GA within 4 weeks before the biopsy. Statistical analyses were done to establish the correlation of NLR and different clinical parameters such as biopsy histology, pre-biopsy PSA, and prostate volume.A total of 652 patients who underwent RTPB for diagnostic purposes with a valid PSA level were included in this study. There was total of 409 (62.7%) benign histology and 243 (37.3%) prostate cancer. There was no significant difference in median NLR between the benign and prostate cancer group (2.00 vs 1.99; P = .29).In the subgroups analysis, there was also no significant difference of median NLR value in clinical significant cancer (defined as Gleason 3 + 4 and above) and benign histology group (NLR 2.00 vs 2.01, P = .41), as well as prostate cancer and benign group according to different pre-biopsy PSA levels: PSA (ug/l) < 4, 4 to 10, 10 to 20, and >20, respectively. (Median NLR 1.34 vs 1.76; 1.97 vs 1.97; 1.97 vs 2.18; 2.18 vs 1.98, P > .05). NLR is neither associated with prostate cancer using logestic regression model nor a strong predictor of the Gleason grade group and D'Amico risk stratification group using ordinal regression model. (P > .05)There was no statistically significant difference of NLR between the benign and prostate cancer group as a whole or in the subgroup analyses for patients who underwent robotic transperineal prostate biopsy. NLR may have a limited role in predicting early-stage prostate cancer.

Urinary Exosomes Diagnosis of Urological Tumors: A Systematic Review and Meta-Analysis

Purpose

Exosomes could be released directly into the urine by the urological tumoral cells, so testing urinary exosomes has great potential for non-invasive diagnosis and monitor of urological tumors. The objective of this study is to systematically review and meta-analysis of urinary exosome for urological tumors diagnosis.

Materials and Methods

A systematic review of the recent English-language literature was conducted according to the PRISMA statement recommendations (CRD42021250613) using PubMed, Embase, Cochrane Library, Web of Science, and Scopus databases up to April 30, 2021. Risk-of-bias assessment was performed according to the QUADAS 2 tool. The true diagnostic value of urinary exosomes by calculating the number of true positive, false positive, true negative, and false negative, diagnoses by extracting specificity and sensitivity data from the selected literature.

Results

Sixteen eligible studies enrolling 3224 patients were identified. The pooled sensitivity and specificity of urinary exosomes as a diagnostic tool in urological tumors were 83% and 88%, respectively. The area under the summary receiver operating characteristic curve was 0.92 (95% CI: 0.89–0.94). Further subgroup analyses showed that our results were stable irrespective of the urinary exosome content type and tumor type.

Conclusion

Urinary exosomes may serve as novel non-invasive biomarkers for urological cancer detection. Future clinical trial designs must validate and explore their utility in treatment decision-making.

Systematic Review Registration

[ https://www.crd.york.ac.uk/prospero/], identifier [CRD42021250613].

Live cell molecular analysis of primary prostate cancer organoids identifies persistent androgen receptor signaling

Prostate Cancer (PC) is a disease with remarkable tumor heterogeneity that often manifests in significant intra-patient variability with regards to clinical outcomes and treatment response. Commonly available PC cell lines do not accurately reflect the complexity of this disease and there is critical need for development of new models to recapitulate the intricate hierarchy of tumor pathogenesis. In current study, we established ex vivo primary patient-derived cancer organoid (PDCO) cultures from prostatectomy specimens of patients with locally advanced PC. We then performed a comprehensive multi-parameter characterization of the cellular composition utilizing a novel approach for live-cell staining and direct imaging in the integrated microfluidic Stacks device. Using orthogonal flow cytometry analysis, we demonstrate that primary PDCOs maintain distinct subsets of epithelial cells throughout culture and that these cells conserve expression of androgen receptor (AR)-related elements. Furthermore, to confirm the tumor-origin of the PDCOs we have analyzed the expression of PC-associated epigenetic biomarkers including promoter methylation of the GSTP1, RASSF1 and APC and RARb genes by employing a novel microfluidic rare-event screening protocol. These results demonstrate that this ex vivo PDCO model recapitulates the complexity of the epithelial tumor microenvironment of multifocal PC using orthogonal analyses. Furthermore, we propose to leverage the Stacks microfluidic device as a high-throughput, translational platform to interrogate phenotypic and molecular endpoints with the capacity to incorporate a complex tumor microenvironment.

Prostate Cancer Radiogenomics-From Imaging to Molecular Characterization

Radiomics and genomics represent two of the most promising fields of cancer research, designed to improve the risk stratification and disease management of patients with prostate cancer (PCa). Radiomics involves a conversion of imaging derivate quantitative features using manual or automated algorithms, enhancing existing data through mathematical analysis. This could increase the clinical value in PCa management. To extract features from imaging methods such as magnetic resonance imaging (MRI), the empiric nature of the analysis using machine learning and artificial intelligence could help make the best clinical decisions. Genomics information can be explained or decoded by radiomics. The development of methodologies can create more-efficient predictive models and can better characterize the molecular features of PCa. Additionally, the identification of new imaging biomarkers can overcome the known heterogeneity of PCa, by non-invasive radiological assessment of the whole specific organ. In the future, the validation of recent findings, in large, randomized cohorts of PCa patients, can establish the role of radiogenomics. Briefly, we aimed to review the current literature of highly quantitative and qualitative results from well-designed studies for the diagnoses, treatment, and follow-up of prostate cancer, based on radiomics, genomics and radiogenomics research.

Precision Medicine Approach in Prostate Cancer

Prostate cancer is the most prevalent type of cancer and the second cause of death in men worldwide. Various diagnostic and treatment procedures are available for this type of malignancy, but High-grade or locally advanced prostate cancers showed the potential to develop to lethal phase that can be causing dead. Therefore, new approaches are needed to prolong patients' survival and to improve their quality of life. Precision medicine is a novel emerging field that plays an essential role in identifying new sub-classifications of diseases and in providing guidance in treatment that is based on individual multi-omics data. Multi-omics approaches include the use of genomics, transcriptomics, proteomics, metabolomics, epigenomics and phenomics data to unravel the complexity of a disease-associated biological network, to predict prognostic biomarkers, and to identify new targeted drugs for individual cancer patients. We review the impact of multi-omics data in the framework of systems biology in the era of precision medicine, emphasising the combination of molecular imaging modalities with highthroughput techniques and the new treatments that target metabolic pathways involved in prostate cancer.

Cribriform pattern does not have a significant impact in Gleason Score ≥7/ISUP Grade ≥2 prostate cancers submitted to radical prostatectomy

INTRODUCTION

The aim of this study was to correlate cribriform pattern (CP) with other parameters in a large prospective series of Gleason score ≥7/ISUP grade ≥2 prostate cancer (PC) cases undergoing radical prostatectomy (RP).

METHODS

This is a prospective single-center study on 210 consecutive patients. Gleason pattern 4 and individual tumor growth patterns determination were performed either in biopsy or in surgical specimens for all patients.

RESULTS

At multiparametric magnetic resonance, a higher percentage of PI-RADS 5 was associated to CP (53.3% vs 17.7%, P = .038). CP was significantly and inversely (r = -0.261; P = .001) correlated with perineural invasion (PNI) but not with other pathological parameters. Kaplan-Meier analysis showed that mean biochemical (Bp) and radiological (Rp) progression-free survival were similar (Bp = χ 0.906; P = .341; Rp = χ 1.880; P = .170) independently to CP. In PNI positive cases, Bp-free survival was higher (χ = 3.617; P = .057) in cases without CP.

CONCLUSIONS

In a homogeneous population excluding ISUP 1 cases, CP showed limited prognostic value. We first described an association with PNI and a prognostic value influenced by PNI status.

Prostate-Specific Antigen Density: A Measurement to Differentiate Benign Hypertrophy of Prostate from Prostate Carcinoma

Background  Determination of isolated prostate-specific antigen (PSA) in asymptomatic individuals has not demonstrated sufficient sensitivity and specificity to be useful in the routine evaluation of prostate disease. To enhance the accuracy of serum PSA we have used a proportion of serum PSA and prostate volume, which we refer to as prostate-specific antigen density (PSAD). Prostate volume in this study was calculated using transrectal ultrasonography (TRUS). Materials and Methods  A total of 106 patients with prostatic disease clinically confined to the prostate glands were evaluated. Results and Observation  The mean PSAD for prostate cancer was 0.15 ± 0.01 while that for benign hypertrophy of the prostate (BPH) was 0.11 ± 0.02 ( p < 0.05). Significant difference ( p < 0.05) was noted in the prostate volume in these two groups with the mean prostate volume measured by TRUS in the BPH to be 53.85 ± 9.71 mL compared with 58.14 ± 7.48 mL in the carcinoma. PSA density of 0.13 ng/mL can be used as a cutoff for the individual in our set-up who should go for prostate biopsy with sensitivity and specificity of over 90%. Conclusion  These results suggest that PSAD may be useful in distinguishing BPH and prostate cancer.

XPC exon15 Lys939Gln variant increase susceptibility to prostate adenocarcinoma: Evidence based on 4306 patients and 4779 controls

BACKGROUND

Previous studies have investigated the correlation between xeroderma pigmentosumcomplementation group C (XPC) variants and prostate adenocarcinoma (PA) risk. Nevertheless, research findings remain inconclusive.

METHODS

We conducted a pooled analysis to obtain a more accurate estimation of the relationship on XPC exon15 Lys939Gln polymorphism with susceptibility to PA. Moreover, in silico tools were employed to investigate the effect of XPC expression on PA patients' survival time.

RESULTS

A total of 4306 patients and 4779 control subjects were assessed. The overall results indicated that XPC Lys939Gln variant was associated with PA risk (recessive genetic model: odds ratio = 1.15, 95% confidence interval = 1.02-1.30, Pheterogeneity= .044, P = .021, I= 45.2), especially in Asian descendants. Population-based studies revealed similar results (odds ratio = 1.15, 95% confidence interval = 1.01-1.32, Pheterogeneity= .146, P = .040, I = 39.0). In silico tools showed that XPC expression in Caucasian patients was lower than in the normal group. No positive association was observed in African patients. PA subjects with high XPC expression had a longer overall survival time than low expression group.

CONCLUSION

Our findings indicated that XPC Lys939Gln variant might contribute to increased PA susceptibility, especially for Asian patients.

Loss of DNA mismatch repair proteins in prostate cancer

Recent studies have suggested an increased risk of prostate cancer in men with Lynch syndrome driven by germline mutations in mismatch repair (MMR) genes. However, the incidence and clinical implication of MMR deficiency in sporadic prostate cancers remain poorly understood. We immunohistochemically stained for MLH1, MSH2, MSH6, and PMS2 in a set of tissue microarray consisting of 220 radical prostatectomy specimens and evaluated the relationship between loss of their expression and available clinicopathological features. MLH1, MSH2, MSH6, and PMS2 were lost in 2 (0.9%), 6 (2.7%), 37 (16.8%), and 27 (12.3%) prostate cancers, respectively. Loss of at least 1 MMR protein was identified in 50 (22.7%) cases. There were no statistically significant associations between MMR deficiency and patient age, family history of prostate cancer, Gleason score, or pT/pN stage. Nonetheless, the levels of preoperative prostate-specific antigen (PSA) were significantly (P = .015) higher in patients with MMR deficiency (mean ± SD: 9.12 ± 9.01 ng/mL) than in those without abnormal MMR (5.76 ± 3.17 ng/mL). There were 15 (6.8%) cases showing loss of at least 2 MMR proteins, which was not significantly associated with PSA level or tumor grade/stage. Additionally, 5 and 2 cases showed losses of at least 3 MMR proteins and all 4 proteins, respectively. Kaplan-Meier analysis revealed no significant associations between loss of MLH1 (P = .373), MSH2 (P = .348), MSH6 (P = .946), or PMS2 (P = .681), or at least 1 (P = .477), 2 (P = .486), or 3 (P = .352) MMR proteins and biochemical recurrence. Further analyses of the data on programmed death-ligand 1 (PD-L1) expression previously stained in the same set of tissue microarray demonstrated associations between loss of ≥2 MMR proteins and a higher rate of PD-L1 expression in cancer cells (17.2% vs 5.2%; P = .033) as well as between cases showing both loss of ≥1 MMR protein(s) and PD-L1 expression in tumor-infiltrating immune cells vs a higher risk of biochemical recurrence (P = .045). MMR protein loss was seen in a subset of prostate cancers. Interestingly, it was associated with significantly higher levels of PSA. Moreover, immunohistochemical detection of MMR proteins together with other proteins, such as PD-L1, might be helpful in predicting tumor recurrence following radical prostatectomy.

Comprehensive analysis of biomarkers for prostate cancer based on weighted gene co-expression network analysis

BACKGROUND

Prostate cancer (PCa) is one of the leading causes of cancer-related death. In the present research, we adopted a comprehensive bioinformatics method to identify some biomarkers associated with the tumor progression and prognosis of PCa.

METHODS

Differentially expressed genes (DEGs) analysis and weighted gene co-expression network analysis (WGCNA) were applied for exploring gene modules correlative with tumor progression and prognosis of PCa. Clinically Significant Modules were distinguished, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to Annotation, Visualization and Integrated Discovery (DAVID). Protein-protein interaction (PPI) networks were used in selecting potential hub genes. RNA-Seq data and clinical materials of prostate cancer from The Cancer Genome Atlas (TCGA) database were used for the identification and validation of hub genes. The significance of these genes was confirmed via survival analysis and immunohistochemistry.

RESULTS

2688 DEGs were filtered. Weighted gene co-expression network was constructed, and DEGs were divided into 6 modules. Two modules were selected as hub modules which were highly associated with the tumor grades. Functional enrichment analysis was performed on genes in hub modules. Thirteen hub genes in these hub modules were identified through PPT networks. Based on TCGA data, 4 of them (CCNB1, TTK, CNN1, and ACTG2) were correlated with prognosis. The protein levels of CCNB1, TTK, and ACTG2 had a degree of differences between tumor tissues and normal tissues.

CONCLUSION

Four hub genes were identified as candidate biomarkers and potential therapeutic targets for further studies of exploring molecular mechanisms and individual therapy on PCa.

Preoperative plasma fatty acid metabolites inform risk of prostate cancer progression and may be used for personalized patient stratification

Background

Little is known about the relationship between the metabolite profile of plasma from pre-operative prostate cancer (PCa) patients and the risk of PCa progression. In this study we investigated the association between pre-operative plasma metabolites and risk of biochemical-, local- and metastatic-recurrence, with the aim of improving patient stratification.

Methods

We conducted a case-control study within a cohort of PCa patients recruited between 1996 and 2015. The age-matched primary cases (n = 33) were stratified in low risk, high risk without progression and high risk with progression as defined by the National Comprehensive Cancer Network. These samples were compared to metastatic (n = 9) and healthy controls (n = 10). The pre-operative plasma from primary cases and the plasma from metastatic patients and controls were assessed with untargeted metabolomics by LC-MS. The association between risk of progression and metabolite abundance was calculated using multivariate Cox proportional-hazard regression and the relationship between metabolites and outcome was calculated using median cut-off normalized values of metabolite abundance by Log-Rank test using the Kaplan Meier method.

Results

Medium-chain acylcarnitines (C6-C12) were positively associated with the risk of PSA progression (p = 0.036, median cut-off) while long-chain acylcarnitines (C14-C16) were inversely associated with local (p = 0.034) and bone progression (p = 0.0033). In primary cases, medium-chain acylcarnitines were positively associated with suberic acid, which also correlated with the risk of PSA progression (p = 0.032, Log-Rank test). In the metastatic samples, this effect was consistent for hexanoylcarnitine, L.octanoylcarnitine and decanoylcarnitine. Medium-chain acylcarnitines and suberic acid displayed the same inverse association with tryptophan, while indoleacetic acid, a breakdown product of tryptophan metabolism was strongly associated with PSA (p = 0.0081, Log-Rank test) and lymph node progression (p = 0.025, Log-Rank test). These data were consistent with the increased expression of indoleamine 2,3 dioxygenase (IDO1) in metastatic versus primary samples (p = 0.014). Finally, functional experiments revealed a synergistic effect of long chain fatty acids in combination with dihydrotestosterone administration on the transcription of androgen responsive genes.

Conclusions

This study strengthens the emerging link between fatty acid metabolism and PCa progression and suggests that measuring levels of medium- and long-chain acylcarnitines in pre-operative patient plasma may provide a basis for improving patient stratification.

Association of Hsa-miR-23a rs3745453 variation with prostate cancer risk among Chinese Han population: A case-control study

Prostate cancer (PCa) is a frequently diagnosed malignant solid tumor in men. The etiology of PCa has been attributed to both environmental and genetic factors. In recent years, many studies have reported that miRNA gene single-nucleotide polymorphisms (SNPs) influence the susceptibility to several diseases such as cancer. To date, the mechanisms of PCa have remained unknown. The main aim of this study was to evaluate the association between PCa susceptibility and miRNA gene SNPs. A total of 156 PCa cases and 188 control subjects were included in this case-control study. The data were collected from hospitalized cases. We collected the demographic characteristic information, which included age, body mass index, tobacco smoking, alcohol consumption, and family history of cancer. Polymorphisms were analyzed by the ligase detection reaction. Unconditional logistic and stratified analyses were used to analyze the association between these SNPs and PCa susceptibility and to calculate the adjusted odds ratios (ORs) and the 95% confidence intervals (CIs). Cox regression model and the log-rank test were used to test the association between genetic variants and the overall survival. We found that miR-23a gene polymorphism rs3745453 carrying CC homozygotes had a 4.16-fold increased risk (95% CI = 1.30-13.25) than those carrying the TT/CT genotypes (P = .02), and the C allele displayed a higher prevalence of PCa than the T allele (OR = 1.68, 95% CI = 1.16-2.45, P = .01). Moreover, miR-23a showed that the homozygous carriers of the C-variant significantly increased the risk of survival rate as compared to the carriers of the TT/CT genotype (OR = 9.67, 95% CI = 2.83-33.09, P = .001). The rs3745453 polymorphism was potentially associated with PCa in the Chinese Han population and had an interactive relationship with the environmental factors.

Olfactomedin 4 downregulation is associated with tumor initiation, growth and progression in human prostate cancer

The olfactomedin 4 (OLFM4) gene has been analyzed as a tumor‐suppressor gene and a putative biomarker in many cancers. In our study, we analyzed the relationship of OLFM4 expression with clinicopathological features and with CpG site methylation in the OLFM4 gene promoter region in human primary prostate adenocarcinoma. OLFM4 protein expression was significantly reduced in prostate cancer tissue compared to adjacent normal tissue and was further significantly reduced in more advanced cancers. Bioinformatic studies with clinical datasets revealed that primary prostate adenocarcinoma patients with reduced OLFM4 mRNA expression exhibited higher Gleason scores and higher preoperative serum prostate‐specific antigen levels, as well as lower recurrence‐free survival. Three of the eight CpG sites in the OLFM4 gene promoter region were hypermethylated in cancerous prostate cells compared to adjacent normal cells, and reduced methylation of eight CpG sites was associated with increased OLFM4 mRNA expression in RWPE1 and PC‐3 cells. Furthermore, knockdown of OLFM4 gene expression was associated with enhanced epithelial–mesenchymal transition (EMT)‐marker expression in RWPE immortalized normal prostate cells. In contrast, restoration of OLFM4 expression in PC‐3 and DU145 prostate cancer cells lacking OLFM4 significantly inhibited both EMT‐marker expression and tumor cell growth in in vitro and in vivo models, indicating that OLFM4 may play a tumor‐suppressor role in inhibiting the EMT program, as well as tumor initiation and growth, in prostate cells. Taken together, these findings suggest that OLFM4 plays an important tumor‐suppressor role in prostate cancer progression and might be useful as a novel candidate biomarker for prostate cancer.

What's new?

Altered expression of the OLFM4 gene appears to be involved in many cancers. In this study of prostate cancers, the authors found that OLFM4 can suppress tumor initiation, growth and progression. Downregulation of OLFM4 was associated with higher serum PSA levels, higher Gleason scores, and lower recurrence‐free survival in prostate cancer patients. These results indicate that OLFM4 may play an important tumor‐suppressor role in the progression of prostate cancer, and may provide a novel prognostic biomarker for prostate cancer treatment.

Prostate MRI, with or without MRI-targeted biopsy, and systematic biopsy for detecting prostate cancer

BACKGROUND

Multiparametric magnetic resonance imaging (MRI), with or without MRI-targeted biopsy, is an alternative test to systematic transrectal ultrasonography-guided biopsy in men suspected of having prostate cancer. At present, evidence on which test to use is insufficient to inform detailed evidence-based decision-making.

OBJECTIVES

To determine the diagnostic accuracy of the index tests MRI only, MRI-targeted biopsy, the MRI pathway (MRI with or without MRI-targeted biopsy) and systematic biopsy as compared to template-guided biopsy as the reference standard in detecting clinically significant prostate cancer as the target condition, defined as International Society of Urological Pathology (ISUP) grade 2 or higher. Secondary target conditions were the detection of grade 1 and grade 3 or higher-grade prostate cancer, and a potential change in the number of biopsy procedures.

SEARCH METHODS

We performed a comprehensive systematic literature search up to 31 July 2018. We searched CENTRAL, MEDLINE, Embase, eight other databases and one trials register.

SELECTION CRITERIA

We considered for inclusion any cross-sectional study if it investigated one or more index tests verified by the reference standard, or if it investigated the agreement between the MRI pathway and systematic biopsy, both performed in the same men. We included only studies on men who were biopsy naïve or who previously had a negative biopsy (or a mix of both). Studies involving MRI had to report on both MRI-positive and MRI-negative men. All studies had to report on the primary target condition.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed the risk of bias using the QUADAS-2 tool. To estimate test accuracy, we calculated sensitivity and specificity using the bivariate model. To estimate agreement between the MRI pathway and systematic biopsy, we synthesised detection ratios by performing random-effects meta-analyses. To estimate the proportions of participants with prostate cancer detected by only one of the index tests, we used random-effects multinomial or binary logistic regression models. For the main comparisions, we assessed the certainty of evidence using GRADE.

MAIN RESULTS

The test accuracy analyses included 18 studies overall.MRI compared to template-guided biopsy: Based on a pooled sensitivity of 0.91 (95% confidence interval (CI): 0.83 to 0.95; 12 studies; low certainty of evidence) and a pooled specificity of 0.37 (95% CI: 0.29 to 0.46; 12 studies; low certainty of evidence) using a baseline prevalence of 30%, MRI may result in 273 (95% CI: 249 to 285) true positives, 441 false positives (95% CI: 378 to 497), 259 true negatives (95% CI: 203 to 322) and 27 (95% CI: 15 to 51) false negatives per 1000 men. We downgraded the certainty of evidence for study limitations and inconsistency.MRI-targeted biopsy compared to template-guided biopsy: Based on a pooled sensitivity of 0.80 (95% CI: 0.69 to 0.87; 8 studies; low certainty of evidence) and a pooled specificity of 0.94 (95% CI: 0.90 to 0.97; 8 studies; low certainty of evidence) using a baseline prevalence of 30%, MRI-targeted biopsy may result in 240 (95% CI: 207 to 261) true positives, 42 (95% CI: 21 to 70) false positives, 658 (95% CI: 630 to 679) true negatives and 60 (95% CI: 39 to 93) false negatives per 1000 men. We downgraded the certainty of evidence for study limitations and inconsistency.The MRI pathway compared to template-guided biopsy: Based on a pooled sensitivity of 0.72 (95% CI: 0.60 to 0.82; 8 studies; low certainty of evidence) and a pooled specificity of 0.96 (95% CI: 0.94 to 0.98; 8 studies; low certainty of evidence) using a baseline prevalence of 30%, the MRI pathway may result in 216 (95% CI: 180 to 246) true positives, 28 (95% CI: 14 to 42) false positives, 672 (95% CI: 658 to 686) true negatives and 84 (95% CI: 54 to 120) false negatives per 1000 men. We downgraded the certainty of evidence for study limitations, inconsistency and imprecision.Systemic biopsy compared to template-guided biopsy: Based on a pooled sensitivity of 0.63 (95% CI: 0.19 to 0.93; 4 studies; low certainty of evidence) and a pooled specificity of 1.00 (95% CI: 0.91 to 1.00; 4 studies; low certainty of evidence) using a baseline prevalence of 30%, systematic biopsy may result in 189 (95% CI: 57 to 279) true positives, 0 (95% CI: 0 to 63) false positives, 700 (95% CI: 637 to 700) true negatives and 111 (95% CI: 21 to 243) false negatives per 1000 men. We downgraded the certainty of evidence for study limitations and inconsistency.Agreement analyses: In a mixed population of both biopsy-naïve and prior-negative biopsy men comparing the MRI pathway to systematic biopsy, we found a pooled detection ratio of 1.12 (95% CI: 1.02 to 1.23; 25 studies). We found pooled detection ratios of 1.44 (95% CI 1.19 to 1.75; 10 studies) in prior-negative biopsy men and 1.05 (95% CI: 0.95 to 1.16; 20 studies) in biopsy-naïve men.

AUTHORS' CONCLUSIONS

Among the diagnostic strategies considered, the MRI pathway has the most favourable diagnostic accuracy in clinically significant prostate cancer detection. Compared to systematic biopsy, it increases the number of significant cancer detected while reducing the number of insignificant cancer diagnosed. The certainty in our findings was reduced by study limitations, specifically issues surrounding selection bias, as well as inconsistency. Based on these findings, further improvement of prostate cancer diagnostic pathways should be pursued.

Metabolomic profiling for the identification of novel diagnostic markers and therapeutic targets in prostate cancer: an update

INTRODUCTION

An altered metabolic regulation is involved in the development and progression of different cancer types. As well as this, many genes associated with tumors are shown to have an important role in control of the metabolism. The incidence of prostate cancer (PCa) is increased in men with metabolic disorders. In particular, obesity is an established risk factor for PCa. An increased body mass index correlates with aggressive disease, and a higher risk of biochemical recurrence and prostate cancer-specific mortality. Increased lipogenesis is also one of the most significant events in PCa metabolism reprogramming. Areas covered: In this article, we provide an updated review of the current understanding of the PCa metabolome and evaluate the possibility of unveiling novel therapeutic targets. Expert opinion: Obesity is an established risk factor for PCa, and an increased BMI correlates with aggressive disease, and a higher risk of biochemical recurrence and prostate cancer-specific mortality. PCa metabolome is characterized by the accumulation of metabolic intermediates and an increased expression of genes in the tricarboxylic acid cycle, the induction of de novo lipogenesis and cholesterogenesis. PCa cells can induce different alterations in their microenvironment by modulating the crosstalk between cancer and stromal cells.

Metabolomics Contributions to the Discovery of Prostate Cancer Biomarkers

Prostate cancer (PCa) is one of the most frequently diagnosed cancers and a leading cause of death among men worldwide. Despite extensive efforts in biomarker discovery during the last years, currently used clinical biomarkers are still lacking enough specificity and sensitivity for PCa early detection, patient prognosis, and monitoring. Therefore, more precise biomarkers are required to improve the clinical management of PCa patients. In this context, metabolomics has shown to be a promising and powerful tool to identify novel PCa biomarkers in biofluids. Thus, changes in polyamines, tricarboxylic acid (TCA) cycle, amino acids, and fatty acids metabolism have been reported in different studies analyzing PCa patients' biofluids. The review provides an up-to-date summary of the main metabolic alterations that have been described in biofluid-based studies of PCa patients, as well as a discussion regarding their potential to improve clinical PCa diagnosis and prognosis. Furthermore, a summary of the most significant findings reported in these studies and the connections and interactions between the different metabolic changes described has also been included, aiming to better describe the specific metabolic signature associated to PCa.

Analysis of differentially expressed genes, clinical value and biological pathways in prostate cancer

The present study aimed to investigate the gene expression changes in prostate cancer (PC) and screen the hub genes and associated pathways of PC progression. The authors employed integrated analysis of GSE46602 downloaded from the Gene Expression Omnibus and The Cancer Genome Atlas databases to identify 484 consensual differentially expressed genes (DEGs) in PC, when compared with adjacent normal tissue samples. Functional annotation and pathway analysis were performed. The protein-protein interaction (PPI) networks and module were constructed. RT-qPCR was used to validate the results in clinical PC samples. Survival analysis of hub genes was performed to explore their clinical value. GO analysis results revealed that DEGs were significantly enriched in negative regulation of nitrobenzene metabolic process, extracellular space and protein homodimerization activity. KEGG pathway analysis results revealed that DEGs were most significantly enriched in focal adhesion. The top 10 hub genes were identified to be hub genes from the PPI network, and the model revealed that these genes were enriched in various pathways, including neuroactive ligand-receptor interaction, p53 and glutathione metabolism signaling pathways. RT-qPCR results validated that expression levels of eight genes (PIK3R1, BIRC5, ITGB4, RRM2, TOP2A, ANXA1, LPAR1 and ITGB8) were consistent with the bioinformatics analysis. ITGB4 and RRM2 with genetic alterations exhibited association with a poorer survival rate, compared with those without alterations. These results revealed that PC-related genes and pathways have an important role in tumor expansion, metastasis and prognosis. In summary, these hub genes and related pathways may act as biomarkers or therapeutic targets for PC.

Next Generation Sequencing of urine exfoliated cells: an approach of prostate cancer microRNAs research

There is emerging evidence that microRNAs (miRNAs) dysregulation is involved in the genesis and the progression of Prostate Cancer (PCa), thus potentially increasing their use in urological clinical practice. This is the first pilot study which utilizes Illumina Deep Sequencing to examine the entire miRNAs spectrum existent in urine exfoliated prostate cells (UEPCs) of PCa patients. A total of 11 male patients with histological diagnosis of PCa were enrolled in the present study. First-catch urine (30 mL) was collected following a prostate massage. Total RNA was extracted from urine and sequenced using an HiSeq2500 System (Illumina). QPCR assay was used to validate the highest NGS results in PCA patients and in age-matched, caucasian men. Remarkably, PCA let-7 family was down-regulated (P < 0.01), compared to the controls. The results of our study support the notion of a relatively high diagnostic value of miRNA family for PCa detection, especially in the let-7 family. The present research confirmed the potential use of miRNAs as non-invasive biomarkers in the diagnosis of PCa, potentially reducing the invasiveness of actual clinical strategy.

Aberrant Promoter Methylation of Protocadherin8 (PCDH8) in Serum is a Potential Prognostic Marker for Low Gleason Score Prostate Cancer

Background

PCDH8 is a newly-discovered suppressor gene that is frequently inactivated by aberrant methylation in several human cancers, including prostate cancer. The identification of PCDH8 methylation can be used as a potential predictive biomarker. Prostate cancer patients with high Gleason score are considered as being at high risk for tumor recurrence and progression, and adjuvant therapy is often routinely performed in clinical practice. In the present study, we did not measure the methylation of PCDH8 in these patients. The main purpose of the present study was to evaluate the clinical significance of PCDH8 methylation in serum of prostate cancer patients with low Gleason score.

Material/Methods

PCDH8 methylation in serum samples of 117 patients and 47 controls was checked by methylation-specific PCR (MSP). Then, we correlated PCDH8 methylation status with the clinicopathological parameters of prostate cancer patients with low Gleason score and patient outcomes.

Results

We found that PCDH8 was more frequently methylated in serum samples of patients with prostate cancer than in controls. PCDH8 methylation was correlated with advanced clinical stage (P=0.021), higher level of preoperative PSA (P=0.008), and positive lymph node metastasis (P=0.010). Moreover, patients with PCDH8 methylation had worse biochemical recurrence (BCR)-free survival (P<0.001) than patients without. Independent prognostic factors for worse BCR-free survival of prostate cancer patients with low Gleason score were: PCDH8 methylation in serum (Exp (B)=3.147, 95% CI: 1.152–7.961, P=0.007), clinical stage (Exp (B)=2.53, 95% CI: 1.032–4.763, P=0.025) and lymph node status (Exp (B)=1.476, 95% CI: 1.107–4.572, P=0.042).

Conclusions

Our study indicated that PCDH8 methylation in serum occurred frequently in prostate cancer patients and was correlated with risk factors for poor outcome. The methylation of PCDH8 in serum is a potential predictive marker for prostate cancer patients with low Gleason score after surgery.

Low serum total testosterone level as a predictor of upstaging and upgrading in low-risk prostate cancer patients meeting the inclusion criteria for active surveillance

Active surveillance (AS) is currently a widely accepted treatment option for men with clinically localized prostate cancer (PCa). Several reports have highlighted the association of low serum testosterone levels with high-grade, high-stage PCa. However, the impact of serum testosterone as a predictor of progression in men with low-risk PCa has been little assessed.

In this study, we evaluated the association of circulating testosterone concentrations with a staging/grading reclassification in a cohort of low-risk PCa patients meeting the inclusion criteria for the AS protocol but opting for radical prostatectomy.

Radical prostatectomy (RP) was performed in 338 patients, eligible for AS according to the following criteria: clinical stage T2a or less, PSA<10ng/ml, two or fewer cancer cores, Gleason score (GS)=6 and PSA density<0.2 ng/mL/cc. Reclassification was defined as upstaging (stage>pT2) and upgrading (GS=7; primary Gleason pattern 4) disease. Unfavorable disease was defined as the occurrence of pathological stage>pT2 and predominant Gleason score 4. Total testosterone was measured before surgery.

Low serum testosterone levels (<300 ng/dL) were significantly associated with upgrading, upstaging, unfavorable disease and positive surgical margins. The addition of testosterone to a base model, including age, PSA, PSA density, clinical stage and positive cancer involvement in cores, showed a significant independent influence of this variable on upstaging, upgrading and unfavorable disease.

In conclusion, our results support the idea that total testosterone should be a selection criterion for inclusion of low-risk PCa patients in AS programs and suggest that testosterone level less than 300 ng/dL should be considered a discouraging factor when a close AS program is considered as treatment option

Serum metabolomics can predict the outcome of first systematic transrectal prostate biopsy in patients with PSA <10 ng/ml

AIM

To assess the predictive value of metabolomic analysis for the presence of prostate cancer (PCa) at first systematic biopsy.

PATIENTS & METHODS

Ninety serum samples from patients with suspicion for PCa were included. Targeted and nontargeted metabolomic analysis was performed.

RESULTS

Six metabolites were combined into a predictive score. A cutoff value of 0.528 for the metabolomic score showed a good accuracy for the prediction of PCa at biopsy (Area under the curve (AUC): 0.779; p < 0.001). These results were validated in a subgroup of patients, showing similar accuracy (p = 0.1). For patients with prostate specific antigen (PSA) less than 10 ng/ml, the score showed a Se 80.95%, Sp 64.52% for the detection of PCa at biopsy.

CONCLUSION

Metabolomic analysis can predict the outcome of the first systematic biopsy.

Structure and biochemical properties of recombinant human dimethylglycine dehydrogenase and comparison to the disease-related H109R variant

The human dimethylglycine dehydrogenase (hDMGDH) is a flavin adenine dinucleotide (FAD)- and tetrahydrofolate (THF)-dependent, mitochondrial matrix enzyme taking part in choline degradation, one-carbon metabolism and electron transfer to the respiratory chain. The rare natural variant H109R causes dimethylglycine dehydrogenase deficiency leading to increased blood and urinary dimethylglycine concentrations. A detailed biochemical and structural characterization of hDMGDH was thus far hampered by insufficient heterologous expression of the protein. In the present study, we report the development of an intracellular, heterologous expression system in Komagataella phaffii (formerly known as Pichia pastoris) providing the opportunity to determine kinetic parameters, spectroscopic properties, thermostability, and the redox potential of hDMGDH. Moreover, we have successfully crystallized the wild-type enzyme and determined the structure to 3.1-Å resolution. The structure-based analysis of our biochemical data provided new insights into the kinetic properties of the enzyme in particular with respect to oxygen reactivity. A comparative study with the H109R variant demonstrated that the variant suffers from decreased protein stability, cofactor saturation, and substrate affinity.

DATABASE

Structural data are available in the PDB database under the accession number 5L46.

The emerging role of obesity, diet and lipid metabolism in prostate cancer

Obesity is associated with an increased risk of a number of serious medical conditions, including cancer. As far as prostate cancer is concerned, obesity is associated with an increased risk of high-grade tumors, which is possibly related to lower androgen levels. Diet may also affect prostate cancer risk since countries with a higher dietary fat intake also present higher prostate cancer mortality rates. Interestingly, prostate cancer is associated with a number of metabolic alterations that may provide valuable diagnostic and therapeutic targets. This review explores the available clinical as well as biological evidence supporting the relationship between obesity, diet, alteration in metabolic pathways and prostate cancer.