The origin of prostate metastases: emerging insights

Small extracellular vesicles: Roles and clinical application in prostate cancer

Prostate cancer is a significant health problem in the United States. It is remarkably heterogenous, ranging from slow growing disease amenable to active surveillance to highly aggressive forms requiring active treatments. Therefore, being able to precisely determine the nature of disease and appropriately match patients to available and/or novel therapeutics is crucial to improve patients' overall outcome and quality of life. Recently small extracellular vesicles (sEVs), a subset of nanoscale membranous vesicles secreted by various cells, have emerged as important analytes for liquid biopsy and promising vehicles for drug delivery. sEVs contain various biomolecules such as genetic material, proteins, and lipids that recapitulate the characteristics and state of their donor cells. The application of existing and newly developed technologies has resulted in an increased depth of knowledge about biophysical structures, biogenesis, and functions of sEVs. In prostate cancer patients, tumor-derived sEVs can be isolated from biofluids, commonly urine and blood. They mediate intercellular signaling within the tumor microenvironment and distal organ-specific sites, supporting cancer initiation, progression, and metastasis. A mounting body of evidence suggests that sEV components can be potent biomarkers for prostate cancer diagnosis, prognosis, and prediction of disease progression and treatment response. Due to enhanced circulation stability and bio-barrier permeability, sEVs can be also used as effective drug delivery carriers to improve the efficacy and specificity of anti-tumor therapies. This review discusses recent studies on sEVs in prostate cancer and is focused on their role as biomarkers and drug delivery vehicles in the clinical management of prostate cancer.

Recent Developments and Application of Mass Spectrometry Imaging in N-Glycosylation Studies: An Overview

Among the most typical posttranslational modifications is glycosylation, which often involves the covalent binding of an oligosaccharide (glycan) to either an asparagine (N-linked) or a serine/threonine (O-linked) residue. Studies imply that the N-glycan portion of a glycoprotein could serve as a particular disease biomarker rather than the protein itself because N-linked glycans have been widely recognized to evolve with the advancement of tumors and other diseases. N-glycans found on protein asparagine sites have been especially significant. Since N-glycans play clearly defined functions in the folding of proteins, cellular transport, and transmission of signals, modifications to them have been linked to several illnesses. However, because these N-glycans' production is not template driven, they have a substantial morphological range, rendering it difficult to distinguish the species that are most relevant to biology and medicine using standard techniques. Mass spectrometry (MS) techniques have emerged as effective analytical tools for investigating the role of glycosylation in health and illness. This is due to developments in MS equipment, data collection, and sample handling techniques. By recording the spatial dimension of a glycan's distribution in situ, mass spectrometry imaging (MSI) builds atop existing methods while offering added knowledge concerning the structure and functionality of biomolecules. In this review article, we address the current development of glycan MSI, starting with the most used tissue imaging techniques and ionization sources before proceeding on to a discussion on applications and concluding with implications for clinical research.

Microbiota and prostate cancer

Prostate cancer remains the most frequently diagnosed non-skin malignancy in male patients, still representing one of the main causes of cancer-related death worldwide. Evidence is mounting that suggests the putative role of microbiota in the carcinogenesis as well as in modulating the efficacy and activity of anticancer treatments (e.g., chemotherapy, immune checkpoint inhibitors, targeted therapies) in a large number of hematological and solid tumors. However, few data are available regarding the interactions between prostate cancer and microbiome so far, in particular in terms of the impact of microbiota on disease development, pathogenesis, and response to medical treatments in this genitourinary malignancy. Herein, we provide an overview of current knowledge, novel insights and emerging therapeutic approaches related to gastrointestinal and genitourinary microbiome in prostate cancer patients, especially focusing on available evidence and published trials on this topic.

The curative effect of androgen deprivation therapy alone is insufficient in high-risk prostate cancer

To compare the outcomes of patients with high-risk prostate cancer treated by primary radical prostatectomy (RP) and primary androgen deprivation therapy (ADT).The study included patients with high-risk or very high-risk prostate cancer. Patients treated with definitive radiation therapy and those with clinical N1 and M1 disease were excluded. The RP group was divided into sub-cohorts of patients treated with ADT and those who received ADT after biochemical recurrence post-RP. Cancer-specific survival (CSS) and overall survival (OS) were analyzed using the Kaplan-Meier method and the Cox proportional hazards model.The study analyzed 859 patients divided into the RP group (n = 654) and ADT group (n = 205). Castration-resistant prostate cancer was detected in 23 (3.5%) patients in the RP group and 43 (21.0%) patients in the ADT group. Mortality cases included 63 (9.6%) patients in the RP group and 91 (44.4%) patients in the ADT group. CSS (P = .0002) and OS (P < .0001) were significantly higher in the RP group than in the ADT group. In the sub-cohort, CSS did not differ significantly between the RP and ADT groups, whereas OS was significantly higher in the RP group than in the ADT group (P < .0001). In the multivariate analysis, primary ADT increased CSS (hazard ratio, 2.068; P = .0498) and OS (hazard ratio, 3.218; P < .0001) compared with RP.In clinically localized high-risk prostate cancer patients, primary RP was associated with better CSS and OS than primary ADT. Comprehensive counseling in this cohort of patients will help the selection of treatment.

In Situ Analysis of N-Linked Glycans as Potential Biomarkers of Clinical Course in Human Prostate Cancer

Prostate cancer is the most common cancer in men worldwide. Despite its prevalence, there is a critical knowledge gap in understanding factors driving disparities in survival among different cohorts of patients with prostate cancer. Identifying molecular features separating disparate populations is an important first step in prostate cancer research that could lead to fundamental hypotheses in prostate biology, predictive biomarker discovery, and personalized therapy. N-linked glycosylation is a cotranslational event during protein folding that modulates a myriad of cellular processes. Recently, aberrant N-linked glycosylation has been reported in prostate cancers. However, the full clinical implications of dysregulated glycosylation in prostate cancer has yet to be explored. Herein, we performed direct on-tissue analysis of N-linked glycans using matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) from tissue microarrays of over 100 patient tumors with over 10 years of follow-up metadata. We successfully identified a panel of N-glycans that are unique between benign and prostate tumor tissue. Specifically, high-mannose as well as tri-and tetra-antennary N-glycans were more abundant in tumor tissue and increase proportionally with tumor grade. Further, we expanded our analyses to examine the N-glycan profiles of Black and Appalachian patients and have identified unique glycan signatures that correlate with recurrence in each population. Our study highlights the potential applications of MALDI-MSI for digital pathology and biomarker discovery for prostate cancer. IMPLICATIONS: MALDI-MSI identifies N-glycan perturbations in prostate tumors compared with benign tissue. This method can be utilized to predict prostate cancer recurrence and study prostate cancer disparities.

Identification of docetaxel-related biomarkers for prostate cancer

Prostate cancer (PCa) which was the second commonly diagnosed malignancy, contributed to the top fifth carcinoma death in men. Nevertheless, the main chemotherapeutic agent docetaxel came to failure due to chemoresistance. Recently, increasing evidence suggested the importance of tumour microenvironment (TME) in PCa. The present study aimed to explore the specific TME in PCa and find biomarkers related to both immune infiltration and docetaxel. The docetaxel-specific genes and differential expression genes comparing PCa with normal control samples were derived using DESeq2 and zinbwave with GSE140440, TCGA and GTEx datasets. Immune-infiltration-related genes were identified using CIBERSORT and co-expression network analysis. Key genes related to both docetaxel and immune infiltrating in PCa, including nine genes, namely ZNF486, IFI6, TMOD2, HSPA4L, ITPR1, LRRC37A7P, APOC1, APOBEC3G, and ITGA2, were determined by overlapping above three gene sets. ITGA2 was then defined as the hub gene for its significant prognostic implications. Further validations conducted on Oncomine, GEO, TISIDB, MSigDB, and The Human Protein Atlas confirmed the docetaxel-specific and immune infiltrating characteristics of ITGA2. To sum up, our findings could provide a better understanding of immune infiltrating and docetaxel-resistance in PCa, mostly, ITGA2 could serve as potential prognosis biomarkers and targets for the combination of docetaxel.

Abiraterone acetate versus bicalutamide in combination with gonadotropin releasing hormone antagonist therapy for high risk metastatic hormone sensitive prostate cancer

The objective of this study was to compare the efficacy of abiraterone acetate with that of bicalutamide in combination with gonadotropin-releasing hormone (GnRH) antagonist treatment for patients with high-risk metastatic hormone-sensitive prostate cancer (mHSPC). A total of 149 patients with mHSPC who underwent treatment at our hospital and affiliated hospitals between December 2013 and July 2020 were retrospectively identified. Fifty patients were administered abiraterone acetate (1000 mg/day) plus prednisolone (5 mg/day) with a GnRH antagonist (degarelix) (group A), and 99 patients were administered bicalutamide (80 mg/day) with a GnRH antagonist (group B). The prostate-specific antigen (PSA) progression-free survival (PSA-PFS) was significantly longer in group A than in group B. Abiraterone acetate therapy and Gleason score were significant independent factors of PSA-PFS. Using propensity score matching, 56 matched patients were obtained. The PSA-PFS (p < 0.001) and overall survival (OS) (p = 0.0071) of patients with high-risk mHSPC were significantly longer in group A of matched patients. Abiraterone acetate therapy and Gleason score were significant independent factors for PSA-PFS in matched patients. The PSA-PFS and OS of patients treated with abiraterone acetate in combination with a GnRH antagonist were significantly better than those treated with bicalutamide.

Exploring the association between metastatic sites and androgen receptor splice variant 7 (AR-V7) in castration-resistant prostate cancer patients: A meta-analysis of prospective clinical trials

BACKGROUND

The Androgen Receptor Splice Variant 7 (AR-V7) has been associated with poor clinical outcomes in patients with castration-resistant prostate cancer (CRPC). Herein, we performed a meta-analysis aimed at systematically exploring the association between metastatic sites and AR-V7 expression in CRPC patients across prospective clinical trials.

METHODS

We retrieved all the relevant prospective clinical trials through PubMed/Medline, Cochrane library, and EMBASE; additionally, proceedings of the main international oncological meetings were also searched for relevant abstracts. Outcomes of interest included metastatic sites (lymph node metastases, any site metastases, visceral metastases, and bone metastases) in AR-V7 positive and AR-V7 negative CRPC patients. Odds Ratios (ORs) and 95 % confidence intervals (CI) were calculated.

RESULTS

Overall, 14 eligible prospective studies involving a total of 1944 CRPC patients (AR-V7 positive: 467; AR-V7 negative: 1477) were included in the analysis. According to our results, no differences between AR-V7 positive and AR-V7 negative CRPC patients were observed in terms of lymph node (OR 1.01; 95 % CI 0.49-2.09) and visceral metastases (OR 1.23; 95 % CI 0.89-1.71). Conversely, AR-V7 positive CRPC patients presented higher rate of any site metastases (OR 2.22; 95 % CI 1.58-3.12) and bone metastases (OR 2.03; 95 % CI 1.42-2.9) compared to AR-V7 negative subjects.

CONCLUSIONS

The results of this meta-analysis, the first in literature to be specifically focused on this topic so far, suggest that AR-V7 positivity may be associated with any site metastases and bone metastases; conversely, no association has been highlighted between AR-V7 expression and lymph node or visceral metastases. Although this meta-analysis should be interpreted with caution due to some limitations, our findings confirm that AR-V7 status could designate a unique and peculiar subtype of PC. Further studies aimed at improving and standardizing AR-V7 detection in clinical trials on CRPC patients are warranted.

Narrative review: predicting future molecular and clinical profiles of prostate cancer in the United States

Prostate cancer represents the most frequent tumor in men, accounting for the 21% of all diagnosed tumors, with 191,930 new cases and 33,330 deaths estimated in 2020. Advanced prostate cancer represents a heterogeneous disease, ranging from hormone naive or hormone sensitive to castration resistant. The therapeutic armamentarium for this disease has been implemented in the last years by novel hormonal therapies and chemotherapies. However, the percentage of patients who achieve complete responses still results negligible. On this scenario, the design of clinical trials investigating new therapeutic approaches represent a dramatic medical need. Predicting cancer incidence may be fundamental to design specific clinical trials, to optimize the allocation of economic resources, and to plan future cancer control programs. ERG, SPOP and DDR genes alterations can act as therapeutic targets in prostate cancer patients and can be tested to identify a gene-selected patient population to enrol in specific trials. According to our predictions, ERG gene fusions will be the most predominant molecular subtype, accounting for 69,050 new cases in 2030. Mutation in SPOP gene will be diagnosed in 16,512 tumors, corresponding to the number of cases associated with alterations in DDR genes (including 7,956 BRCA2 mutated tumors). In this article, we analyzed and discussed the future molecular and clinical profiles of prostate cancer in the United States, aimed to describe a series of distinct subpopulations and to quantify potential clinical trial candidates in the next years.

The Adipose Tissue at the Crosstalk Between EDCs and Cancer Development

Obesity is a major public health concern at the origin of many pathologies, including cancers. Among them, the incidence of gastro-intestinal tract cancers is significantly increased, as well as the one of hormone-dependent cancers. The metabolic changes caused by overweight mainly with the development of adipose tissue (AT), insulin resistance and chronic inflammation induce hormonal and/or growth factor imbalances, which impact cell proliferation and differentiation. AT is now considered as the main internal source of endocrine disrupting chemicals (EDCs) representing a low level systemic chronic exposure. Some EDCs are non-metabolizable and can accumulate in AT for a long time. We are chronically exposed to low doses of EDCs able to interfere with the endocrine metabolism of the body. Importantly, several EDCs have been involved in the genesis of obesity affecting profoundly the physiology of AT. In parallel, EDCs have been implicated in the development of cancers, in particular hormone-dependent cancers (prostate, testis, breast, endometrium, thyroid). While it is now well established that AT secretes adipocytokines that promote tumor progression, it is less clear whether they can initiate cancer. Therefore, it is important to better understand the effects of EDCs, and to investigate the buffering effect of AT in the context of progression but also initiation of cancer cells using adequate models recommended to uncover and validate these mechanisms for humans. We will review and argument here the potential role of AT as a crosstalk between EDCs and hormone-dependent cancer development, and how to assess it.

Metastasis-directed therapy for oligometastatic urological tumours: still no second-hand news

For patients presenting with limited metastatic disease burden, known as the oligometastatic state of disease, a more aggressive treatment approach targeting the new or progressive metastatic lesions might improve patient outcome, with no or only limited toxicity to be expected from the treatment. This review provides an overview of the existing evidence and on-going trials on oligometastatic disease and metastasis-directed therapy in the field of renal, bladder and prostate cancer.

Key Role of Obesity in Genitourinary Tumors with Emphasis on Urothelial and Prostate Cancers

Background: In human populations, a certain amount of data correlate obesity/body mass index (BMI) with urothelial cancer (UC) and prostate cancer (PCa) occurrence, however this is not fully elucidated at all stages of disease. In an attempt to shed light on uncertain areas in such field, in the present review we illustrate the main molecular mechanisms linking obesity and cancer, focusing on the correlation between obesity and tumor risk, disease progression and response to chemo- and immunotherapy in patients with UC and the predictive/prognostic role of obesity in PCa patients treated with the currently available therapeutic approaches. Methods: We did a large-scale literature search on existing scientific websites focusing on keywords "obesity", "body mass index (BMI)", "urothelial cancer", "prostate cancer", "docetaxel", "cabazitaxel", "abiraterone acetate", "enzalutamide", and "radium223". Results: Many adipocytes-induced molecules support tumor proliferation through activation of various cellular pathways. The available evidence in the postoperative setting do the role of BMI in oncological outcomes prediction still not completely clear. Likewise, in metastatic UC patients controversial results link the role of obesity/BMI with clinical outcomes of tumor response to chemotherapy. Adipose stromal cells recruitment, induced by PCa cells, from white adipose tissue to the tumor sites inducing cell invasiveness was associated with poor survival. Conflicting data, although more oriented towards a better survival outcome, resulted in obese patients treated with docetaxel. In PCa cell-lines a certain cabazitaxel chemo resistance adipose stromal cells (ASC)-mediated was demonstrated. In metastatic castration-resistant PCa patients with high BMI (>25 kg/m2) receiving abiraterone acetate there were significant worse survival outcomes, while in enzalutamide patients BMI did not affect survival outcome. In radium 223 patients higher BMI significantly correlated with favorable overall survival. Conclusions: The main focus of this review was to understand the interplay between obesity/BMI and UC/PCa. Several pathogenic cellular pathways exploring the issue are discussed, opening the way to challenging tailored treatments on the basis of BMI. Improving the knowledge of molecular connections between obesity and UC and PCa could favor the development of new therapies likely reducing chemo- and immunotherapy drug resistance.

Oncological effect of palliative transurethral resection of the prostate in patients with advanced prostate cancer: a propensity score matching study

PURPOSE

We investigated the oncologic effect of palliative transurethral resection of the prostate (pTURP) in patients with prostate cancer who received primary androgen deprivation therapy.

METHODS

We reviewed 614 patients, including 83 who underwent pTURP; those with incidental prostate cancer were excluded. Patients were divided into the TURP group and non-TURP group. Propensity score matching was performed for comorbidity, initial prostate-specific antigen (PSA), TNM stage, and Gleason score (GS). The Kaplan-Meier method was used to confirm castration-resistant prostate cancer (CRPC), cancer-specific survival (CSS), and overall survival (OS). Cox regression was performed to confirm factors affecting CSS.

RESULTS

Before matching, the TURP group had a worse TNM stage (p < 0.01) and GS (p = 0.028) and larger prostate volume (50.1 vs. 39.0 cc, p = 0.005) than the non-TURP group. The most common reason for pTURP was acute urinary retention. After matching, the TURP group showed worse outcomes in CRPC (p = 0.003), CSS (p = 0.003), and OS (p = 0.026). In multivariate analysis, factors for predicting CSS were a positive core percent [hazard ratio (HR) 1.015, p = 0.0272], GS (10 vs. ≤8; HR 6.716, p = 0.0008), and TURP within 3 months after biopsy (HR 2.543, p = 0.0482). The resection weight (HR 1.000, p = 0.9730), resection time (HR 1.000, p = 0.3670), and blood transfusion (HR 0.630, p = 0.1860) were not associated with CSS.

CONCLUSIONS

The oncologic effect of pTURP as cytoreductive operation seems to be limited. Patients who had to receive pTURP due to cancer-related symptoms, especially early necessity of pTURP (within 3 months after biopsy), showed worse clinical courses; therefore, they should be treated more carefully and actively.

Increased cancer stem cell invasion is mediated by myosin IIB and nuclear translocation

Despite many advances in the treatment of breast cancer, it remains one of the leading causes of death among women. One hurdle for effective therapy is the treatment of the highly invasive and tumorigenic subpopulation of tumors called cancer stem cells (CSCs). CSCs, when stimulated with EGF, migrate through a physiological 3D collagen matrix at a higher velocity than non-stem cancer cells (non-SCCs). This increased invasion is due, in part, by an enhanced nuclear translocation ability of CSCs. We observed no difference between CSC and non-SCC in cellular migration rates on a 2D surface. Furthermore, during transwell migration using large diameter transwell pores, both CSC and non-SCC populations migrated with similar efficiency. However, when challenged with more restrictive transwells, CSCs were dramatically more capable of transwell migration. These results implicate nuclear translocation as a major rate limiting factor for CSC dissemination. We further show that non-muscle myosin IIB is critical for this enhanced nuclear translocation and the ability for cancer stem cells to efficiently migrate through restrictive 3D environments. These studies suggest that cytoskeletal elements upregulated in CSCs, such as myosin IIB, may be valuable targets for intervention in cancer stem cell dispersal from tumors.

Tumor microenvironment heterogeneity: challenges and opportunities

The tumor microenvironment (TME) has been recognized as an integral component of malignancies in breast and prostate tissues, contributing in confounding ways to tumor progression, metastasis, therapy resistance and disease recurrence. Major components of the TME are immune cells, fibroblasts, pericytes, endothelial cells, mesenchymal stroma/stem cells (MSCs), and extracellular matrix (ECM) components. Herein, we discuss the molecular and cellular heterogeneity within the TME and how this presents unique challenges and opportunities for treating breast and prostate cancers.

Molecular determinants of prostate cancer metastasis

Metastatic cancer remains largely incurable and fatal. The general course of cancer, from the initiation of primary tumor formation and progression to metastasis, is a multistep process wherein tumor cells at each step must display specific phenotypic features. Distinctive capabilities required for primary tumor initiation and growth form the foundation, and sometimes may remain critical, for subsequent metastases. These phenotypic features must remain easily malleable during the acquisition of additional capabilities unique and essential to the metastatic process such as dissemination to distant tissues wherein tumor cells interact with foreign microenvironments. Thus, the metastatic phenotype is a culmination of multiple genetic and epigenetic alterations and subsequent selection for favorable traits under the pressure of ever-changing tumor microenvironments. Although our understanding of the molecular programs that drive cancer metastasis are incomplete, increasing evidence suggests that successful metastatic colonization relies on the dissemination of cancer stem cells (CSCs) with tumor-regenerating capacity and adaptive programs for survival in distant organs. In the past 2-3 years, a myriad of novel molecular regulators and determinants of prostate cancer metastasis have been reported, and in this Perspective, we comprehensively review this body of literature and summarize recent findings regarding cell autonomous molecular mechanisms critical for prostate cancer metastasis.

Low vitamin D status is associated with inflammation in patients with prostate cancer

Vitamin D deficiency has been associated with increased risks of prostate cancer. Nevertheless, the mechanisms remain unclear. The aim of this study was to analyze the association among prostate cancer, vitamin D status and inflammation. Sixty patients with newly diagnosed prostate cancer and 120 age-matched controls were recruited for this study. Vitamin D status was evaluated and serum inflammatory molecules were measured. Serum 25-(OH)D was lower in patients with prostate cancer. Moreover, serum 25(OH)D was lower in patients with severe prostate cancer than patients with mild and moderate prostate cancer. By contrast, serum C-reactive protein (CRP) and interleukin (IL)-8, two inflammatory molecules, were elevated in patients with prostate cancer. Serum 25-(OH)D was negatively correlated with serum CRP and IL-8 in patients with prostate cancer. Additional analysis showed that the percentage of vitamin D receptor positive nucleus in the prostate was reduced in patients with prostate cancer. By contrast, the percentage of nuclear factor kappa B p65-positive nucleus was elevated in patients with prostate cancer. Our results provide evidence that there is an association among prostate cancer, vitamin D deficiency and inflammatory signaling. Inflammation may be an important mediator for prostate cancer progression in patients with low vitamin D status.

Down-regulation of miR-605 promotes the proliferation and invasion of prostate cancer cells by up-regulating EN2

AIMS

MicroRNA served as inhibitor for gene expression in various cancers. This study aimed to investigate the role of miR-605 and EN2 in prostate cancer (PCa).

MATERIALS AND METHODS

In this research, the expression of miR-605 and EN2 protein in PCa tissues and cells were determined by qRT-PCR and western blot, respectively. The cell proliferation was measured by Cell Counting Kit-8 (CCK-8) and the tumor cell invasion assay was accomplished with transwell system. Flow cytometry was used to analyze the cell cycle. The endogenous expression of miR-605 and EN2 was modulated by recombinant plasmids and cell transfection. Dual luciferase reporter assay was performed to determine the interaction between miR-605 and EN2 in PCa cells.

KEY FINDINGS

The expression of miR-605 was lower in PCa tissue and cells than that in normal tissues and cells, while the expression of EN2 was just the opposite. Down-regulation of the EN2 by siRNA inhibited the proliferation and invasion of PC3 cells, and the cell cycle was arrested in G0/G1 phase. EN2 regulated the expression of E-cadherin and Vimentin through Snail and EN2 regulated the cell cycle and cell proliferation via PI3K/AKT pathway. MiR-605 inhibited the proliferation and invasion of PCa cells through targeting EN2.

SIGNIFICANCE

EN2 is negatively regulated by miR-605, and down-regulation of miR-605 promotes the proliferation and invasion of PCa cells by up-regulating EN2, which leads to PCa development and progression.

Extranodal extension of lymph node metastasis influences recurrence in prostate cancer: a systematic review and meta-analysis

The extranodal extension (ENE) of nodal metastasis involves the extension of neoplastic cells through the lymph node capsule into the perinodal adipose tissue. This morphological feature has recently been indicated as an important prognostic factor in various cancer types, but its role in prostate cancer is still unclear. We aimed to clarify it, performing the first meta-analysis on this issue, comparing prognostic parameters in surgically treated, node-positive prostate cancer patients with (ENE+) vs. without (ENE-) ENE. Data were summarized using risk ratios (RRs) for number of deaths/recurrences and hazard ratios (HRs), with 95% confidence intervals (CI), for the time-dependent risk related to ENE positivity. Six studies followed-up 1,113 patients with N1 prostate cancer (658 ENE+ vs. 455 ENE-) for a median of 83 months. The presence of ENE was associated with a significantly higher risk of biochemical recurrence (RR = 1.15; 95%CI: 1.03-1.28; I2 = 0%; HR = 1.40, 95%CI: 1.12-1.74; I2 = 0%) and "global" (biochemical recurrence and distant metastasis) recurrence (RR = 1.15; 95%CI: 1.04-1.28; I2 = 0%; HR = 1.41, 95%CI: 1.14-1.74; I2 = 0%). ENE emerged as a potential prognostic moderator, earmarking a subgroup of patients at higher risk of recurrence. It may be considered for the prognostic stratification of metastatic patients. New possible therapeutic approaches may explore more in depth this prognostic parameter.

Release of urinary extracellular vesicles in prostate cancer is associated with altered urinary N-glycosylation profile

AIM

Nowadays, extracellular vesicles are of great interest in prostate cancer (PCa) research. Asparagine (N)-linked glycosylation could play a significant role in the pathological mechanism of these vesicles. We investigated if prostatic protein N-glycosylation profiles were related to urinary vesicle-associated prostate-specific antigen (PSA) extractability and if this parameter showed diagnostic potential for PCa.

METHODS

Urinary extracellular vesicles were visualised using transmission electron microscopy. Urinary extracellular vesicles extraction by means of n-butanol allowed determination of urinary vesicle-associated PSA extractability. Diagnostic value was assessed between benign prostate hyperplasia (BPH; n=122) and patients with PCa (n=85). Additionally, correlation with urine N-glycosylation was assessed.

RESULTS

Urinary extracellular vesicles with a diameter of approximately 100 nm were more abundantly present in urine of patients with PCa versus patients with BPH resulting in a higher vesicle-associated PSA extraction ratio (p<0.001). Next, vesicle-associated PSA extraction ratio was correlated to biantennary core-fucosylation (p=0.003). Finally, vesicle-associated PSA extraction ratio proved beneficial in PCa diagnosis, next to serum PSA and the urinary glycosylation marker (p=0.021).

CONCLUSIONS

The urinary vesicle-associated PSA extraction ratio is increased in PCa which is a direct result of the abundant presence of extracellular vesicles in urine of patients with PCa. The urinary vesicle-associated PSA extraction ratio was associated with changes in N-glycoforms and showed diagnostic potential. Further research is warranted to unravel the pathological link between N-glycosylation and extracellular vesicles in cancer, as well as to assess the prognostic value of this biomarker.

The role of exosomes in cancer metastasis

Exosomes are small membrane vesicles with a size ranging from 40 to 100nm. They can serve as functional mediators in cell interaction leading to cancer metastasis. Metastasis is a complex multistep process of cancer cell invasion, survival in blood vessels, attachment to and colonization of the host organ. Exosomes influence every step of this cascade and can be targeted by oncological treatment. This review highlights the role of exosomes in the various steps of the metastatic cascade and how exosome dependent pathways can be targeted as therapeutic approach or used for liquid biopsies.

The Relationship between Obesity, Prostate Tumor Infiltrating Lymphocytes and Macrophages, and Biochemical Failure

BACKGROUND

Obesity reflects a chronic inflammatory environment that may contribute to prostate cancer progression and poor treatment outcomes. However, it is not clear which mechanisms drive this association within the tumor microenvironment. The aim of this pilot study was to examine prostatic inflammation via tumor infiltrating lymphocytes and macrophages characterized by obesity and cancer severity.

METHODS

We studied paraffin-embedded prostatectomy tissue from 99 participants (63 non-obese and 36 obese) from the Study of Clinical Outcomes, Risk and Ethnicity (University of Pennsylvania). Pathologists analyzed the tissue for type and count of lymphocytes and macrophages, including CD3, CD8, FOXP3, and CD68. Pathology data were linked to clinical and demographic variables. Statistical analyses included frequency tables, Kruskal-Wallis tests, Spearman correlations, and multivariable models.

RESULTS

We observed positive univariate associations between the number of CD68 cells and tumor grade (p = 0.019). In multivariable analysis, CD8 counts were associated with time to biochemical failure (HR = 1.09, 95% CI = 1.004-1.192, p-value = 0.041.) There were no differences in lymphocytes or macrophages by obesity status or BMI.

CONCLUSIONS

The number of lymphocytes and macrophages in the tumor microenvironment did not differ by obesity status. However, these inflammation markers were associated with poor prostate cancer outcomes. Further examination of underlying mechanisms that influence obesity-related effects on prostate cancer outcomes is warranted. Such research will guide immunotherapy protocols and weight management as they apply to diverse patient populations and phenotypes.