Obesity, metabolic syndrome, and prostate cancer

Effect of metformin on incidence, recurrence, and mortality in prostate cancer patients: integrating evidence from real-world studies

PURPOSE

Metformin has been suggested to reduce the risk of cancer. However, previous studies have been inconsistent regarding the relationship between metformin use and the risk of occurrence of prostate cancer (PCa). The purpose of this study was to assess the effect of metformin on clinical outcomes in patients with PCa in a meta-analysis and to explore the possible dose-response relationship.

METHODS

A systematic literature search was conducted in 10 electronic databases and 4 registries. The combined relative risks (RRs) were calculated using a random-effects model with 95% confidence interval (CIs) to assess the effect of metformin on the risk of PCa. Relevant subgroup analyses and sensitivity analyses were performed.

RESULTS

The across studies results show that metformin use associated with lower incidence of PCa (RR: 0.82, 95% CI: 0.74-0.91). Metformin use was also found to reduce PCa recurrence, but the results were not statistically significant (RR: 0.97, 95% CI: 0.81-1.15). Metformin use was not associated with PCa mortality (RR: 0.94, 95% CI: 0.81-1.09). The results of subgroup analyses indicated that the type of study was a cohort study and the population came from both Asia and Europe showed that taking metformin reduced the incidence of PCa. A linear correlation was found between the duration of metformin use and its protective effect.

CONCLUSIONS

This meta-analysis revealed an independent correlation between metformin use and reduced incidence of PCa. Metformin use was not associated with either PCa recurrence rate or mortality. Furthermore, the effect of metformin on PCa incidence was found to be related to duration.

Testosterone levels at diagnosis: A key predictor of overall survival among patients with prostate cancer

Background and Objective

The exact relationship between testosterone levels at diagnosis and prostate cancer (PCa) prognosis remains inadequately explored. The objective was to determine whether serum testosterone levels at the time of PCa diagnosis are associated with overall survival.

Patients and Methods

The study cohort involved 2544 PCa patients, divided into three groups; normal (>10.4 nmol/L), grey zone (8.0-10.4 nmol/L) and low (2.0-8.0 nmol/L) serum testosterone groups. Survival outcomes were analysed using Kaplan-Meier curves and Cox regression models.

Results

The analysis revealed an increased risk of death among patients with low testosterone levels compared to those with normal levels in uni- (HR = 1.67, 95% CI: 1.37-2.05, p < 0.001) and multivariable-adjusted (HR = 1.58, 95% CI: 1.24-1.98, p < 0.001) analysis. Sensitivity analysis on patients with normal glucose metabolism revealed similar results (HR = 1.93, CI: 1.48-2.51, p < 0.001), as well as after stratified with age below 70 years (HR = 1.55, 95% CI: 1.02-2.36, p < 0.001) and over 70 years (HR = 1.83, 95% CI: 1.46-2.28, p < 0.001.) There was no difference in survival between the grey zone compared to other testosterone groups. The retrospective design limits our ability to infer causality.

Conclusion

Low testosterone at the time of PCa diagnosis is an independent predictor of overall survival. Findings highlight the potential of testosterone for prognostic evaluation in PCa.

Does insulin resistance predict prostate cancer? Results from the Reduction by Dutasteride of Prostate Cancer (REDUCE) Trial

PURPOSE

Prior studies testing the association between insulin resistance (IR) and prostate cancer (PC) risk are inconsistent. We examined the association between Homeostatic Assessment of Insulin Resistance (HOMA-IR; calculated from fasting baseline insulin and glucose) and PC in REDUCE, a 4-year randomized trial of dutasteride vs. placebo for PC prevention.

EXPERIMENTAL DESIGN

All patients had prestudy negative biopsies and underwent study mandated biopsies at 2 and 4 years regardless of prostate-specific antigen. Multivariable logistic regression models were used to investigate the associations between log-transformed or categorized HOMA-IR scores and PC risk. Multinominal regression was used to assess associations between HOMA-IR scores and tumor grade (low grade [grade group 1]; high-grade [grade groups 2-5]).

RESULTS

Among 5430 REDUCE participants (1212 with PC; 856 low- and 356 high-grade), higher HOMA-IR was associated with lower PC risk (log-HOMA-IR: OR, 0.89; 95% CI, 0.80-0.99; p = .03; categorized HOMA-IR: p-trend = .04). When stratified by grade, HOMA-IR was significantly associated with reduced low-grade PC risk (log-HOMA-IR: OR, 0.84; 95% CI , 0.74-0.94; p = .003; categorized HOMA-IR: p-trend = .002) but was unrelated to high-grade PC (log-HOMA-IR: OR, 1.02; 95% CI, 0.86-1.21; p = .81; categorized HOMA-IR: p-trend = .26). Results were similar in placebo and treatment arms.

CONCLUSIONS

In summary, higher HOMA-IR was associated with a reduced risk of low-grade PC but was not associated with high-grade disease. The mechanisms to explain these findings are unclear.

Genetically predicted 91 circulating inflammatory proteins in relation to risk of urological malignancies: a Mendelian randomization study

BACKGROUND

Urological malignancies, including kidney, bladder, and prostate cancer, are major health concerns worldwide. Inflammation has been implicated in the pathogenesis of these cancers, and circulating inflammatory proteins may play a role in their development. However, the causal relationship between specific plasma proteins and urological malignancies remains unclear.

METHODS

We performed a two-sample Mendelian randomization (MR) analysis using summary statistics from genome-wide association studies (GWAS). Instrumental variables representing genetic variants associated with circulating inflammatory proteins were used to infer causality on the risk of kidney, bladder, and prostate cancer. Four MR methods were utilized to provide robust effect estimates.

RESULTS

Our analysis identified several plasma proteins associated with a lower risk of kidney and bladder cancer, including Eukaryotic translation initiation factor 4E-binding protein 1, Caspase 8, Natural killer cell receptor 2B4, and Tumor necrosis factor ligand superfamily member 12. However, after adjusting for multiple testing, these associations did not remain statistically significant. For prostate cancer, CUB domain-containing protein 1 and Interleukin-10 receptor subunit beta were found to be protective, while Glial cell line-derived neurotrophic factor and SIR2-like protein 2 were identified as risk factors. After FDR adjustment, none of the inflammatory proteins were found to be significantly associated with a lower risk of prostate cancer.

CONCLUSION

Our findings suggest that certain plasma proteins may be involved in the development of urological malignancies. Mendelian randomization provides a useful framework for investigating causal relationships between inflammatory proteins and urological cancers, offering potential insights into their underlying biology and therapeutic targets.

Exploring the role of the inflammasomes on prostate cancer: Interplay with obesity

Obesity is a weight-related disorder characterized by excessive adipose tissue growth and dysfunction which leads to the onset of a systemic chronic low-grade inflammatory state. Likewise, inflammation is considered a classic cancer hallmark affecting several steps of carcinogenesis and tumor progression. In this regard, novel molecular complexes termed inflammasomes have been identified which are able to react to a wide spectrum of insults, impacting several metabolic-related disorders, but their contribution to cancer biology remains unclear. In this context, prostate cancer (PCa) has a markedly inflammatory component, and patients frequently are elderly individuals who exhibit weight-related disorders, being obesity the most prevalent condition. Therefore, inflammation, and specifically, inflammasome complexes, could be crucial players in the interplay between PCa and metabolic disorders. In this review, we will: 1) discuss the potential role of each inflammasome component (sensor, molecular adaptor, and targets) in PCa pathophysiology, placing special emphasis on IL-1β/NF-kB pathway and ROS and hypoxia influence; 2) explore the association between inflammasomes and obesity, and how these molecular complexes could act as the cornerstone between the obesity and PCa; and, 3) compile current clinical trials regarding inflammasome targeting, providing some insights about their potential use in the clinical practice.

Germline mutations in prostate cancer: a systematic review of the evidence for personalized medicine

BACKGROUND

The goal of precision medicine in prostate cancer (PCa) is to individualize the treatment according to the patient's germline mutation status. PCa has a very high rate of genetic predisposition compared with other cancers in men, with an estimated rate of cancers ascribable to hereditary factors of 5-15%.

METHODS

A systematic search (PubMed, Web of Science, and ClinicalTrials.gov) of English literature from 2000 to 2022, using the keywords "prostate cancer", "germline mutations", "family history", and "inheritance" was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

RESULTS

The search identified 980 publications. Of these, 200 papers were removed before screening (duplicates, non-English literature, and publication year before 2000) and 245 records were excluded after title/abstract screening. Finally, 50 articles were included in the final analysis. We analyze the latest evidence on the genetic basis of PCa predisposition and clinical implications for more personalized screening protocols and therapeutic management of this high-prevalent cancer.

DISCUSSION

Emerging data show that germline mutations in homologous recombination genes (BRCA1/2, ATM, CHECK2), in mismatch repair genes (MLH1, MLH2, MSH6), and other additional genes are associated with the development and aggressiveness of PCa. Germline testing and genetic counseling have increasingly important implications in cancer screening and therapeutic decisions making for patients affected by PCa. Patients with localized PCa and some gene mutations are more likely to develop aggressive cancer, so active treatment may be preferable to active surveillance for these patients. Moreover, in patients with metastatic PCa, these gene alterations may be useful biomarkers for predicting response to specific therapy such as PARP inhibitors, recently approved for the treatment of metastatic castration-resistant PCa. The evidence supports recent guidelines and recommendations considering germline genetic testing for patients with a positive family history of PCa or men with high risk or metastatic disease.

High-fat diet induces C-reactive protein secretion, promoting lung adenocarcinoma via immune microenvironment modulation

To understand the effects of a high-fat diet (HFD) on lung cancer progression and biomarkers, we here used an inducible mutant epidermal growth factor receptor (EGFR)-driven lung cancer transgenic mouse model fed a regular diet (RD) or HFD. The HFD lung cancer (LC-HFD) group exhibited significant tumor formation and deterioration, such as higher EGFR activity and proliferation marker expression, compared with the RD lung cancer (LC-RD) group. Transcriptomic analysis of the lung tissues revealed that the significantly changed genes in the LC-HFD group were highly enriched in immune-related signaling pathways, suggesting that an HFD alters the immune microenvironment to promote tumor growth. Cytokine and adipokine arrays combined with a comprehensive analysis using meta-database software indicated upregulation of C-reactive protein (CRP) in the LC-HFD group, which presented with increased lung cancer proliferation and metastasis; this was confirmed experimentally. Our results imply that an HFD can turn the tumor growth environment into an immune-related pro-tumorigenic microenvironment and demonstrate that CRP has a role in promoting lung cancer development in this microenvironment.

Tissue immunoexpression of IL-6 and IL-18 in aging men with BPH and MetS and their relationship with lipid parameters and gut microbiota-derived short chain fatty acids

Recent studies indicate that inflammation is one of the causes of the development of benign prostatic hyperplasia (BPH). Inflammation may result from past infections, metabolic disorders, but also from the state of functioning of the intestinal microbiota. The aim of the study was to assess whether the diagnostic lipid parameters for metabolic syndrome and short-chain fatty acids (SCFAs) are related to the immunoexpression of interleukins in prostate tissue with benign hyperplasia. The study involved 103 men with BPH, who were divided into two groups depending on the presence of MetS. We analysed tissue immunoexpression of two proinflammatory interleukins: IL-6, which is known to be involved in the development of BPH, and IL-18, which has not been analysed so far. The results of our study indicate that men with BPH + MetS in the stroma of the prostate have a significantly higher overall percentage of IL-6+ cells compared to men without MetS (p = 0.034). The analysis of IL-18 immunoexpression in prostate tissue indicated that in men with BPH + MetS, the glandular part of the prostate had a significantly higher percentage of cells with strong IL-18 expression (p = 0.040). We also noticed a relationship between tissue expression of IL-6 and IL-18 and lipid parameters (TG and HDL). We conclude that lipid disorders occurring in men with BPH increase inflammation in the prostate gland. Moreover, it has also been demonstrated for the first time that, indirectly, through SCFAs, the gut microbiota can act to prevent or create an inflammatory microenvironment in the prostate gland.

Obesity and prostate cancer - microenvironmental roles of adipose tissue

Obesity is known to have important roles in driving prostate cancer aggressiveness and increased mortality. Multiple mechanisms have been postulated for these clinical observations, including effects of diet and lifestyle, systemic changes in energy balance and hormonal regulation and activation of signalling by growth factors and cytokines and other components of the immune system. Over the past decade, research on obesity has shifted towards investigating the role of peri-prostatic white adipose tissue as an important source of locally produced factors that stimulate prostate cancer progression. Cells that comprise white adipose tissue, the adipocytes and their progenitor adipose stromal cells (ASCs), which proliferate to accommodate white adipose tissue expansion in obesity, have been identified as important drivers of obesity-associated cancer progression. Accumulating evidence suggests that adipocytes are a source of lipids that are used by adjacent prostate cancer cells. However, results of preclinical studies indicate that ASCs promote tumour growth by remodelling extracellular matrix and supporting neovascularization, contributing to the recruitment of immunosuppressive cells, and inducing epithelial-mesenchymal transition through paracrine signalling. Because epithelial-mesenchymal transition is associated with cancer chemotherapy resistance and metastasis, ASCs are considered to be potential targets of therapies that could be developed to suppress cancer aggressiveness in patients with obesity.

Association between oral cavity cancer and metabolic syndrome

PURPOSE

Few studies have been conducted on the association between oral cavity cancer and metabolic diseases. This study aimed to investigate the relationship between oral cavity cancer and metabolic diseases.

METHODS

This cohort study used the database of the Korean National Health Insurance Service, which contains medical data of 97% of the Korean population. Oral cavity cancer occurred in a total of 2718 patients. Metabolic syndrome was defined according to IDF criteria. The Cox proportional hazard regression model was used.

RESULTS

The HR for oral cavity cancer in patients with metabolic syndrome was 1.113(95% CI 1.006-1.232), which was significantly higher than that in normal patients, especially in males (p = 0.0386). When the number of metabolic syndrome factors was ≥ 3, the HR of oral cavity cancer was 1.191(95% CI 1.026-1.383), which was significantly higher than that of 0 metabolic syndrome factors, especially in males (p = 0.0218). When the number of metabolic syndrome factors was ≥ 3, the HR for oral cavity cancer was 1.439(95% CI 1.066-1.942), which was significantly higher than that of 0 metabolic syndrome factors, especially in males aged < 50 years (p = 0.0173).

CONCLUSION

Metabolic syndrome increases the risk of oral cavity cancer only in males. In addition, the incidence of oral cavity cancer increased as the number of factors constituting metabolic syndrome increased, only in young males aged < 50 years. Thus, metabolic syndrome is an important risk factor for oral cavity cancer, particularly in young males.

Circadian rhythm in prostate cancer: time to take notice of the clock

The circadian clock is an evolutionary molecular product that is associated with better adaptation to changes in the external environment. Disruption of the circadian rhythm plays a critical role in tumorigenesis of many kinds of cancers, including prostate cancer (PCa). Integrating circadian rhythm into PCa research not only brings a closer understanding of the mechanisms of PCa but also provides new and effective options for the precise treatment of patients with PCa. This review begins with patterns of the circadian clock, highlights the role of the disruption of circadian rhythms in PCa at the epidemiological and molecular levels, and discusses possible new approaches to PCa therapy that target the circadian clock.

Serum cholesterol and the risk of developing hormonally driven cancers: A narrative review

Although cholesterol has been hypothesized to promote cancer development through several potential pathways, its role in the risk of developing hormonally driven cancer is controversial. This literature review summarizes evidence from the highest quality studies to examine the consistency and strength of the relationship between serum cholesterol parameters and incidence of hormonally driven cancer. Articles were identified using EMBASE. Longitudinal observational studies published between January 2000 and December 2020 were considered for inclusion. The endpoint of interest was incident prostate, ovary, breast, endometrium, and uterine cancers. In total, 2732 reports were identified and screened; 41 studies were included in the review. No associations were found for ovarian cancer. Most endometrial cancer studies were null. The majority (76.9%) of studies reported no association between cholesterol and prostate cancer. Data on breast cancer were conflicting, associations limited, and effect sizes modest. Our results do not provide evidence for a clear association between cholesterol and different types of incident, hormonally driven reproductive cancers. Future studies should investigate the impact of lipid-lowering therapy.

The effect of lowering cholesterol through diet on serum prostate-specific antigen levels: A secondary analysis of clinical trials

IMPORTANCE

Statins appear to lower serum prostate-specific antigen (PSA) and improve prostate cancer (PCa) outcomes through cholesterol-dependent and independent mechanisms. While dietary modifications have an established role in serum cholesterol reduction, whether diet-driven cholesterol reductions yield similar PCa benefits to that observed with statins is unclear. We aimed to study the effect of dietdriven cholesterol reduction on serum PSA and estimated-PCa risk.

METHODS

A total of 291 men from six published randomized controlled trials of dietary interventions were included. Men were aged ≥40 years, free of PCa, and had baseline PSA <10.0 ng/mL. Participants received one of four diets (high-fiber, low-glycemic index, low-glycemic load, or cholesterol-lowering) for 8-24 weeks. The primary outcome evaluated the association between change from baseline low-density lipoprotein cholesterol (LDL-C) and PSA. How cholesterol reduction modified PCa risk was estimated using the Prostate Cancer Prevention Trial (PCPT) risk calculator (limited to age ≥55 years, baseline PSA ≥1.0 ng/mL).

RESULTS

Baseline PSA was 0.90 ng/mL (interquartile range [IQR] 0.55-1.60) and LDL-C was 90 mg/dL (IQR 69-125). In multivariate regression, PSA decreased 1.9% (95% confidence interval [CI] 0.55-3.2, p=0.005) per 10% reduction in LDL-C. This regression was greater in men with baseline PSA ≥2.0 ng/mL (-5.4%, 95% CI 2.2-8.6] per 10% LDL-C reduction, p-interaction=0.001). In men with estimable PCPT risk, statin-comparable LDL-C reductions (≥15%) reduced PSA by 12% (p<0.001) and estimated PCa risk by 6.5% (p=0.005).

CONCLUSIONS

This is the first study to show that serum cholesterol reduction through dietary interventions significantly lowered serum PSA and estimated PCa risk. Whether cholesterol-lowering diets improve PCa outcomes warrants investigation.

Metabolomic Profile in Patients with Malignant Disturbances of the Prostate: An Experimental Approach

Purpose To identify metabolites in humans that can be associated with the presence of malignant disturbances of the prostate.

Methods In the present study, we selected male patients aged between 46 and 82 years who were considered at risk of prostate cancer due to elevated levels of prostate-specific antigen (PSA) or abnormal results on the digital rectal examination. All selected patients came from two university hospitals (Hospital Universitario del Valle and Clínica Rafael Uribe Uribe) and were divided into 2 groups: cancer (12 patients) and non-cancer (20 patients). Cancer was confirmed by histology, and none of the patients underwent any previous treatment. Standard protocols were applied to all the collected blood samples. The resulting plasma samples were kept at -80°C, and a profile of each one was acquired by nuclear magnetic resonance (NMR) using established experiments. Multivariate analyses were applied to this dataset, first to establish the quality of the data and identify outliers, and then, to model the data.

Results We included 12 patients with cancer and 20 without it. Two patients were excluded due to contamination with ethanol. The remaining ones were used to build an Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) model (including 15 non-cancer and 10 cancer patients), with acceptable discrimination (Q2 = 0.33). This model highlighted the role of lactate and lipids, with a positive association of these two metabolites and prostate cancer.

Conclusions The primary discriminative metabolites between patients with and without prostate cancer were lactate and lipids. These might be the most reliable biomarkers to trace the development of cancer in the prostate.

Racial Disparities in Prostate Cancer: Evaluation of Diet, Lifestyle, Family History, and Screening Patterns

BACKGROUND

Racial disparities in prostate cancer incidence and mortality rates are considerable. We previously found in the Health Professionals Follow-up Study (HPFS) that African-American men had an 80% higher prostate cancer risk than White men. With 21 additional years of follow-up and four-fold increase in cases, we undertook a contemporary analysis of racial differences in prostate cancer incidence and mortality in HPFS.

METHODS

For 47,679 men, we estimated HRs and 95% confidence intervals (CI) for the association between race and risk of prostate cancer through 2016 using Cox proportional hazards regression. Multivariable models (mHR) were adjusted for lifestyle, diet, family history, and PSA screening collected on biennial questionnaires.

RESULTS

6,909 prostate cancer cases were diagnosed in White, 89 in African-American, and 90 in Asian-American men. African-Americans had higher prostate cancer incidence (mHR = 1.31; 95% CI, 1.06-1.62) and mortality (mHR = 1.67; 95% CI, 1.00-2.78), and lower PSA screening prevalence than White men. The excess risk was greater in the pre-PSA screening era (HR = 1.68; 95% CI, 1.14-2.48) than the PSA screening era (HR = 1.20; 95% CI, 0.93-1.56). Asian-Americans had lower prostate cancer risk (mHR = 0.74; 95% CI, 0.60-0.92), but similar risk of fatal disease compared with white men.

CONCLUSIONS

Racial differences in prostate cancer incidence and mortality in HPFS are not fully explained by differences in lifestyle, diet, family history, or PSA screening.

IMPACT

Additional research is necessary to address the disproportionately higher rates of prostate cancer in African-American men.

Regulation and role of CAMKK2 in prostate cancer

In 2011, CAMKK2, the gene encoding calcium/calmodulin-dependent kinase kinase 2 (CAMKK2), was demonstrated to be a direct target of the androgen receptor and a driver of prostate cancer progression. Results from multiple independent studies have confirmed these findings and demonstrated the potential role of CAMKK2 as a clinical biomarker and therapeutic target in advanced prostate cancer using a variety of preclinical models. Drug development efforts targeting CAMKK2 have begun accordingly. CAMKK2 regulation can vary across disease stages, which might have important implications in the use of CAMKK2 as a biomarker. Moreover, new non-cell-autonomous roles for CAMKK2 that could affect tumorigenesis, metastasis and possible comorbidities linked to disease and treatment have emerged and could present novel treatment opportunities for prostate cancer.

Dysregulation of the miRNome unveils a crosstalk between obesity and prostate cancer: miR-107 asa personalized diagnostic and therapeutic tool

Prostate-specific antigen (PSA) is the gold-standard marker to screen prostate cancer (PCa) nowadays. Unfortunately, its lack of specificity and sensitivity makes the identification of novel tools to diagnose PCa an urgent medical need. In this context, microRNAs (miRNAs) have emerged as potential sources of non-invasive diagnostic biomarkers in several pathologies. Therefore, this study was aimed at assessing for the first time the dysregulation of the whole plasma miRNome in PCa patients and its putative implication in PCa from a personalized perspective (i.e., obesity condition). Plasma miRNome from a discovery cohort (18 controls and 19 PCa patients) was determined using an Affymetrix-miRNA array, showing that the expression of 104 miRNAs was significantly altered, wherein six exhibited a significant receiver operating characteristic (ROC) curve to distinguish between control and PCa patients (area under the curve [AUC] = 1). Then, a systematic validation using an independent cohort (135 controls and 160 PCa patients) demonstrated that miR-107 was the most profoundly altered miRNA in PCa (AUC = 0.75). Moreover, miR-107 levels significantly outperformed the ability of PSA to distinguish between control and PCa patients and correlated with relevant clinical parameters (i.e., PSA). These differences were more pronounced when considering only obese patients (BMI > 30). Interestingly, miR-107 levels were reduced in PCa tissues versus non-tumor tissues (n = 84) and in PCa cell lines versus non-tumor cells. In vitro miR-107 overexpression altered key aggressiveness features in PCa cells (i.e., proliferation, migration, and tumorospheres formation) and modulated the expression of important genes involved in PCa pathophysiology (i.e., lipid metabolism [i.e., FASN] and splicing process). Altogether, miR-107 might represent a novel and useful personalized diagnostic and prognostic biomarker and a potential therapeutic tool in PCa, especially in obese patients.

Metabolic syndrome and prostate cancer in Afro-Caribbean men

INTRODUCTION AND OBJECTIVES

Metabolic syndrome (MetS) is a group of risk factors that increases the likelihood of developing cardiovascular diseases. Although suggested, the relationship between MetS and prostate cancer (PCa) is still inconclusive. Very few studies have addressed this question in populations of African descent, which are disproportionately affected by PCa. This study aimed to assess the prevalence of MetS among incident cases of Afro-Caribbean PCa and estimate its association with adverse clinicopathological features and the risk of biochemical recurrence (BCR) after radical prostatectomy (RP).

MATERIALS AND METHODS

We included 285 consecutive patients with incident cases of PCa attending the University Hospital of Guadeloupe (French West Indies). MetS was evaluated at the time of diagnosis by collecting information on blood pressure, glycaemic status, triglyceride and high-density lipoprotein cholesterol levels, and obesity through various surrogates, including two waist circumference indicators (≤94 cm, ≥102 cm), the waist-to-hip ratio (≥0.95), and body mass index (BMI; ≥30 kg/m² ). We followed 245 patients who underwent RP as primary treatment of localized PCa.

RESULTS

The prevalence of MetS varied greatly, from 31.6% to 16.4%, when a waist circumference ≥94 cm or BMI were used as obesity surrogates, respectively. No significant associations were found between MetS, regardless of the obesity criteria employed, and the risk of adverse pathological features or BCR.

CONCLUSIONS

The high variability in MetS resulting from the diversity of obesity criteria used may explain the discordant associations reported in the literature. Further studies using strict and uniform criteria to define MetS on homogeneous ethnic groups are encouraged to clarify the association, if any, between MetS and PCa outcomes.

Analysis of exosome-derived microRNAs reveals insights of intercellular communication during invasion of breast, prostate and glioblastoma cancer cells

MiRNAs represent a mechanism that regulates gene expression in many pathological conditions. Exosomes are known to be secreted from all types of cells, and the exosomes-released molecules are crucial messengers that can regulate cellular processes. We investigated the miRNAs content of exosomes released by cancer cells during the invasion . An invasion stimulus has been generated through scratches created on the confluent cells of cancer cell lines: glioblastoma, breast and prostate cancers.Several miRNAs were found to be significantly differentially abundant during the cell invasion , both in common among different cell lines and exclusive. Understanding the language codes among cells involved in invasion can lead to the development of therapies that can inhibit cellular communication, slowing or eventually stopping their activity.

Association of metabolic syndrome with prostate cancer diagnosis and aggressiveness in patients undergoing transrectal prostate biopsy

INTRODUCTION AND OBJECTIVE

Even though the only established risk factors for prostate cancer (PCa) are age, ethnic origin and family history, there are data suggesting that environmental factors, such as the presence of metabolic syndrome (MetS), may also play a role in the etiology of the disease. The aim of this study is to correlate MetS with PCa diagnosis and Gleason score (GS) in patients undergoing transrectal ultrasound guided prostate biopsy.

MATERIALS AND METHODS

This is a prospective, single-center study including 378 patients who underwent transrectal ultrasound guided prostate biopsy in our department during the years from 2018 to 2019. Patients were divided into two groups according to the presence of PCa. Group A included 197 patients diagnosed with PCa while Group B consisted of 181 patients without PCa in their biopsy result. Multiple variables such as the presence of MetS and its components were evaluated in correlation to the presence of PCa and PCa characteristics. Statistical analysis was performed using the IBM SPSS Statistics v.23 program.

RESULTS

Mean PSA value was 8.7 ng/dl in the PCa group and 7.1 ng/dl in the non PCa group, respectively. MetS was diagnosed in 108 patients (54.8%) with PCa and 80 patients (44.2%) without PCa and the difference was statistically significant. Hypertriglyceridemia was the MetS component with statistically higher frequency in PCa patients. Furthermore, the prevalence of MetS was higher in higher Gleason score PCa (GS ≥ 4+3) patients vs lower Gleason score PCa (GS ≤ 3+4) patients. More specifically, MetS, hypertriglyceridemia, and low HDL levels were independent factors associated with higher Gleason score PCa (GS ≥ 4+3).

CONCLUSIONS

Patients suffering from MetS who undergo prostate biopsy present with higher rates of PCa diagnosis and higher GS in comparison with patients with a normal metabolic profile.

Dietary Carbohydrate Intake Glycemic Index and Glycemic Load and the Risk of Prostate Cancer among Iranian Men: A Case-Control Study

Previous studies have presented a few evidences on the relationship between dietary carbohydrate intake, glycemic index (GI), glycemic load (GL), with the prostate cancer risk. We performed a case-control study to evaluate these associations in 50 men with histologically confirmed prostate cancer and 100 control men. Odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were derived using logistic regression. The fully adjusted ORs for the top vs. the bottom quartile were 15.02 (P trend = 0.004), 1.04 (P trend = 0.003), and 10.35 (P trend = 0.002) for carbohydrate intake, GI and GL, respectively. Significant associations with prostate cancer remained only among men with reduced fiber intake for carbohydrate intake, GI and GL and among those had increased fiber intake for GI. These findings support the hypothesis that diet with high carbohydrate, GI and GL enhance risk of prostate cancer.

A novel prognostic risk factor for patients undergoing radical prostatectomy: Triglyseride-glucose index

BACKGROUND

Obesity and metabolic syndrome are growing health problems in western countries. Recently reported triglyseride-glucose (TyG) index is a reliable and accessible indicator of metabolic syndrome. TyG index could be used as a indicator of a prognostic risk factor for metabolic syndrome-related cancers.

OBJECTIVES

To investigate the prognostic role of TyG index on oncological outcomes in patients undergoing radical prostatectomy.

DESIGN, SETTING AND PARTICIPANTS

Data from 200 men who underwent radical prostatectomy were used.

OUTCOME MEASUREMENTS AND STATSITICAL ANALYSE

TyG was calculated based on TyG index = Ln [TG (mg/dL) FPG (mg/dL)/2] formula. Patients were divided into two groups according to the 8.55 level as cut-off value for TyG index. Laboratory results, oncological outcomes and survivals were comparised statistically between groups.

RESULTS

Mean ages of patients were 64.32 ± 6.1 years and median follow-up time was 61.6 ± 35 (range 4-140) month. Biochemical recurrens was observed in 42 (21%) patients. Positive correlation between TyG index, body mass index, waist circumference, prostate biopsy gleason score, clinical T stage, positive surgical margin, pathological T stage and biochemical recurrence were observed. There was no statistical significance in terms of survival between groups.

CONCLUSION

Association between TyG index and prostate cancer may facilitate to predict unfavorable prognostic factors of radical prostatectomy. Increased TyG index may use as a predictive marker of positive surgical margin status before radical prostatectomy, BCR, advanced cT and pT stages after radical prostatectomy or worse biopsy gleason score in clinical practice.

Pancreatic Cancer Exposome Profile to Aid Early Detection and Inform Prevention Strategies

Pancreatic cancer (PCa) is associated with a poor prognosis and high mortality rate. The causes of PCa are not fully elucidated yet, although certain exposome factors have been identified. The exposome is defined as the sum of all environmental factors influencing the occurrence of a disease during a life span. The development of an exposome approach for PCa has the potential to discover new disease-associated factors to better understand the carcinogenesis of PCa and help with early detection strategies. Our systematic review of the literature identified several exposome factors that have been associated with PCa alone and in combination with other exposures. A potential inflammatory signature has been observed among the interaction of several exposures (i.e., smoking, alcohol consumption, diabetes mellitus, obesity, and inflammatory markers) that further increases the incidence and progression of PCa. A large number of exposures have been identified such as genetic, hormonal, microorganism infections and immune responses that warrant further investigation. Future early detection strategies should utilize this information to assess individuals' risk for PCa.

Comprehensive transcriptome analysis of colorectal cancer risk of hyperglycemia in humans

BACKGROUND

Epidemiological studies have found that hyperglycemia, is an independent risk factor for colorectal cancer (CRC), increasing colon cancer incidence and affecting the recurrence, metastasis, and prognosis in colon cancer patients. However, the intercorrelation between hyperglycemia and CRC risk is still unknown, In the present study, we sought to determine whether gene markers, which act in CRC with hyperglycemia, are silenced in CRC without hyperglycemia.

METHODS

In order to characterize the mechanism of functional genes associated with CRC with hyperglycemia, A total 24 CRC and matched controls were sequenced. Through bioinformatics analysis includes differential expression analysis, functional enrichment, new isoform prediction and alternative splicing event identification to found biomarker genes related to CRC development.

RESULTS

CRC patients with hyperglycemia were compared with patients without hyperglycemia, and we found that 21 genes were upregulated and 27 were downregulated. Further study showed that these genes are possibly of key genes involved in CRC development with hyperglycemia, such as mannan-binding lectin-associated serine protease 3 (MASP3), which has an immunological role in the activation of the complement system. Based on our comprehensive analysis, a cis-regulatory network for hyperglycemic CRC was reconstructed.

CONCLUSIONS

Protein-protein interactions revealed the mechanisms of molecules involved in the interaction of hyperglycemia and cancer development. Our results provide further information on the metabolic pathway interaction with cancer pathways and elucidated the mechanisms of hyperglycemic factors function in cancer development from a transcriptomic perspective.

Metabolic syndrome biomarkers and prostate cancer risk in the UK Biobank

We investigated the association between metabolic syndrome (MetS) and its components and risk of prostate cancer (PCa) in a cohort of men enrolled in the UK Biobank. Our study cohort included 220 622 PCa-free men with baseline measurements of triglycerides (TGs), HDL-cholesterol (HDL), glycated hemoglobin (HbA1c), blood pressure (BP), and waist circumference (WC). Multivariable Cox proportional hazards regression was used to analyze associations with PCa for: individual metabolic components (TG, HDL, HbA1c, BP, WC), combinations of two and three components, and MetS overall (three or more components). We conducted mediation analyses to examine potential hormonal and inflammatory pathways (total testosterone [TT], C-reactive protein [CRP], insulin-like growth factor 1 [IGF-1]) through which MetS components may influence PCa risk. A total of 5409 men in the study developed PCa during a median follow-up of 6.9 years. We found no significant association between MetS and PCa risk (hazard ratio [HR] = 0.99, 95% confidence interval [CI] = 0.92-1.06). No associations were found with PCa risk and individual measurements of TG, HDL, BP, or WC. However, an inverse association was observed with elevated HbA1c (≥42 mmol/mol) (HR = 0.89, 95% CI = 0.79-0.98). Consistent inverse associations were observed between HbA1c and risk of PCa. Mediation analysis revealed TT, CRP, and IGF-1 as potential mediating factors for this association contributing 10.2%, 7.1%, and 7.9% to the total effect, respectively. Overall MetS had no association with PCa risk. However, a consistent inverse association with PCa risk was found for HbA1c. This association may be explained in part through hormonal and inflammatory pathways.

Inflammation as a Driver of Prostate Cancer Metastasis and Therapeutic Resistance

Simple Summary

Prostate cancer is the most common malignancy in men, with a high mortality rate when disease progresses to metastasis and therapeutic resistance. Evidence implicates inflammation as a driver of prostate cancer risk and has a significant impact on processes in the tumor microenvironment that facilitate progression to advanced therapeutically resistant disease. In this review, we discuss the sources of inflammation in the prostate, the functional contribution of the critical inflammatory effectors to prostate cancer initiation and metastatic progression, and the therapeutic challenges that they impose on treatment of advanced disease and overcoming therapeutic resistance. Full understanding of the role of inflammation in prostate cancer progression to advanced metastatic disease and tumor relapse will aid in the development of personalized predictive biomarkers and therapy to reduce the burden and mortality in prostate cancer patients.

Abstract

Prostate cancer is the most common malignancy among men, and progression to metastasis and the emergence of therapeutically resistant disease confers a high mortality rate. Growing evidence implicates inflammation as a driver of prostate cancer development and progression, resulting in increased cancer risk for prostate cancer. Population-based studies revealed that the use of antinflammatory drugs led to a 23% risk reduction prostate cancer occurrence, a negative association that was stronger in men who specifically used COX-2 inhibitors. Furthermore, patients that were taking aspirin had a 21% reduction in prostate cancer risk, and further, long-term users of daily low dose aspirin had a 29% prostate cancer risk reduction as compared to the controls. Environmental exposure to bacterial and viral infections, exposure to mutagenic agents, and genetic variations predispose the prostate gland to inflammation, with a coordinated elevated expression of inflammatory cytokines (IL-6, TGF-β). It is the dynamics within the tumor microenvironment that empower these cytokines to promote survival and growth of the primary tumor and facilitate disease progression by navigating the immunoregulatory network, phenotypic epithelial-mesenchymal transition (EMT), angiogenesis, anoikis resistance, and metastasis. In this review, we discuss the sources of inflammation in the prostate, the functional contribution of the critical inflammatory effectors to prostate cancer initiation and metastatic progression, and the therapeutic challenges that they impose on treatment of advanced disease and overcoming therapeutic resistance. Growing mechanistic evidence supports the significance of inflammation in localized prostate cancer, and the systemic impact of the process within the tumor microenvironment on disease progression to advanced therapeutically-resistant prostate cancer. Rigorous exploitation of the role of inflammation in prostate cancer progression to metastasis and therapeutic resistance will empower the development of precise biomarker signatures and effective targeted therapeutics to reduce the clinical burden and lethal disease in the future.

EGFR-upregulated LIFR promotes SUCLG2-dependent castration resistance and neuroendocrine differentiation of prostate cancer

Neuroendocrine (NE) differentiation is a well-recognized phenotypic change of prostate cancer after androgen deprivation therapy (ADT), and it ultimately develops into an aggressive subset of this disease. However, the contribution of signaling pathways that lead to metabolic disorders and NE differentiation of prostate cancer remains unclear. In this study, we identified that ADT induced upregulation of the succinate-CoA ligase GDP-forming beta subunit (SUCLG2), which regulates succinate metabolism and NE differentiation of prostate cancer. We demonstrated a connection that upregulation of epidermal growth factor receptor (EGFR)-leukemia inhibitory factor receptor (LIFR) signaling induced SUCLG2 expression in prostate cancer cells. The LIFR is upregulated by nuclear EGFR, which acts as a transcriptional regulator, directly binds to the LIFR promoter, and drives NE differentiation and glycolysis of prostate cancer. LIFR upregulation is associated with SUCLG2, which increased succinate synthesis and enzymatic activities of mitochondrial nucleoside diphosphate kinase (NDPK) in prostate cancer cells. Knockdown of SUCLG2 suppressed NE differentiation in cultured cells and reduced prostate tumor growth in a xenograft model. Analysis of prostate tissue samples showed increased intensity of nuclear EGFR associated with the LIFR and SUCLG2 in castration-resistant prostate cancer tumors. Our study provides a mechanism whereby ADT upregulates EGFR-LIFR signaling that activates SUCLG2, which subsequently stimulates the metabolic changes associated with NE differentiation and aggressive prostate cancer phenotype.

Relationship of self-reported body size and shape with risk for prostate cancer: A UK case-control study

INTRODUCTION

Previous evidence has suggested a relationship between male self-reported body size and the risk of developing prostate cancer. In this UK-wide case-control study, we have explored the possible association of prostate cancer risk with male self-reported body size. We also investigated body shape as a surrogate marker for fat deposition around the body. As obesity and excessive adiposity have been linked with increased risk for developing a number of different cancers, further investigation of self-reported body size and shape and their potential relationship with prostate cancer was considered to be appropriate.

OBJECTIVE

The study objective was to investigate whether underlying associations exist between prostate cancer risk and male self-reported body size and shape.

METHODS

Data were collected from a large case-control study of men (1928 cases and 2043 controls) using self-administered questionnaires. Data from self-reported pictograms of perceived body size relating to three decades of life (20's, 30's and 40's) were recorded and analysed, including the pattern of change. The associations of self-identified body shape with prostate cancer risk were also explored.

RESULTS

Self-reported body size for men in their 20's, 30's and 40's did not appear to be associated with prostate cancer risk. More than half of the subjects reported an increase in self-reported body size throughout these three decades of life. Furthermore, no association was observed between self-reported body size changes and prostate cancer risk. Using 'symmetrical' body shape as a reference group, subjects with an 'apple' shape showed a significant 27% reduction in risk (Odds ratio = 0.73, 95% C.I. 0.57-0.92).

CONCLUSIONS

Change in self-reported body size throughout early to mid-adulthood in males is not a significant risk factor for the development of prostate cancer. Body shape indicative of body fat distribution suggested that an 'apple' body shape was protective and inversely associated with prostate cancer risk when compared with 'symmetrical' shape. Further studies which investigate prostate cancer risk and possible relationships with genetic factors known to influence body shape may shed further light on any underlying associations.

The Relationship Between Prostate Cancer and Metformin Consumption: A Systematic Review and Meta-analysis Study

INTRODUCTION

Prostate cancer is the most common malignant cancer in men worldwide and after lung cancer, it is the second leading cause of cancer mortality in men. The purpose of this study was to investigate the relationship between prostate cancer and metformin consumption in men.

METHODS

The current study is a systematic and meta-analysis review based on the PRISMA statement. To access the studies of domestic and foreign databases, Iran Medex, SID, Magiran, Iran Doc, Medlib, ProQuest, Science Direct, PubMed, Scopus, Web of Science and the Google Scholar search engine were searched during the 2009- 2018 period for related keywords. In order to evaluate the heterogeneity of the studies, Q test and I2 indicator were used. The data were analyzed using the STATA 15.1 software.

RESULTS

In 11 studies with a sample size of 877058, the odds ratio of metformin consumption for reducing prostate cancer was estimated at 0.89 (95%CI: 0.67-1.17). Meta-regression also showed there was no significant relationship between the odds ratio and the publication year of the study. However, there was a significant relationship between the odds ratio and the number of research samples.

CONCLUSION

Using metformin in men reduces the risk of prostate cancer but it is not statistically significant.

Serum Adipokines as Predictors for the Outcome of Prostate Biopsies at Early Stage Prostate Cancer Diagnosis

Purpose

Elevated adipokines in patients with obesity and metabolic syndrome have been linked to increased risk of prostate cancer (PCa). The association between select serum adipokines and the outcome of prostate biopsies alone and in combination with clinical parameters at different early stages of PCa was investigated.

Patients and methods

Clinical data and serum adipokines were retrieved from three retrospective cohorts representing men at different points in PCa detection: 1. Subjects with no prior biopsies (n=1061), 2. subjects with a prior negative biopsy (REDUCE trial, control arm) (n=1209), 3. subjects with low-risk PCa on active surveillance (AS) (n=154). Adipokines were chosen based on an unpublished pilot study and included: Resistin, Tumor Necrosis Factor-α, Interleukin-6, Monocyte Chemoattractant Protein-1, Hepatocyte Growth Factor, and Nerve Growth Factor. The primary outcome was the absence of PCa on biopsy and the secondary outcome was diagnosis of low-risk PCa fitting the criteria for continuing AS. Logistic regression analysis was used to assess the association of adipokines and negative and/or low-risk PCa at prostate biopsy.

Results

In men with no prior prostate biopsy or with prior negative biopsy, adipokines were not predictors of prostate biopsy outcomes on multivariable regression analysis controlling for known clinical variables. In the AS cohort, MCP-1 and Resistin were significant predictors of biopsy outcome on multivariable analysis (OR 0.20, 95% CI: 0.05–0.85, p= 0.03 & OR 0.30, 95% CI: 0.10 −0.86, p= 0.03).

Conclusion

Our findings do not support a strong role for adipokines for predicting the outcome of prostate biopsies at any early stage in PCa diagnosis.

Hyperinsulinemia and thyroid peroxidase antibody in Chinese patients with papillary thyroid cancer

This study aimed to investigate if hyperinsulinemia and/or insulin resistance was correlated with the occurrence of papillary thyroid cancer (PTC) in a group of Chinese patients. 258 inpatients were included in the study. According to the postoperative pathology results, all subjects were divided into PTC (n = 153) and control groups (with benign thyroid nodules, n = 105). Body mass index (BMI), fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), thyroid-stimulating hormone (TSH), FT4, FT3, thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb), serum uric acid (UA), and lipid levels. Fasting insulin levels, HOMA-IR values, TPOAb levels, serum TSH levels, and serum uric acid levels in the PTC group were higher than those in the control group (p < 0.05). However, no significant differences in age, gender, BMI, history of hypertension, and the levels of fasting plasma glucose, FT3, FT4, TGAb, total cholesterol, triglyceride, low-density lipoprotein, and high-density lipoprotein were observed between the two groups (p > 0.05). After the multiple logistic regression analysis, the occurrence of PTC was positively associated with fasting insulin (odds ratio [OR] = 1.048, 95% confidence interval [CI]: 1.003-1.096, p = 0.037) and TPOAb levels (OR = 1.001, 95% CI: 1.000-1.002, p = 0.032). Moreover, TPOAb level was positively correlated with vague margin (r = 0.126, p = 0.045) and negatively correlated with homogeneous echo (r = -0.179, p = 0.004). However, fasting insulin levels were not correlated with pathological characteristics of PTC. Hyperinsulinemia and higher TPOAb levels might be the risk factors of PTC, but not disease severity in Chinese patients.

Downregulation of CENPF Remodels Prostate Cancer Cells and Alters Cellular Metabolism

Metabolic alterations in prostate cancer (PC) are associated with progression and aggressiveness. However, the underlying mechanisms behind PC metabolic functions are unknown. The authors' group recently reported on the important role of centromere protein F (CENPF), a protein associated with the centromere-kinetochore complex and chromosomal segregation during mitosis, in PC MRI visibility. This study focuses on discerning the role of CENPF in metabolic perturbation in human PC3 cells. A series of bioinformatics analyses shows that CENPF is one gene that is strongly associated with aggressive PC and that its expression is positively correlated with metastasis. By identifying and reconstructing the CENPF network, additional associations with lipid regulation are found. Further untargeted metabolomics analysis using gas chromatography-time-of-flight-mass spectrometry reveals that silencing of CENPF alters the global metabolic profiles of PC cells and inhibits cell proliferation, which suggests that CENPF may be a critical regulator of PC metabolism. These findings provide useful scientific insights that can be applied in future studies investigating potential targets for PC treatment.

Body mass index and prostate cancer risk in the Carotene and Retinol Efficacy Trial

The aim of this study was to investigate the association between BMI (kg/m) and prostate cancer risk. BMI is a modifiable lifestyle factor and may provide a unique opportunity for primary prevention of prostate cancer if a causal association exists. Data from 11 886 men from the Carotene and Retinol Efficacy Trial (CARET, 1985-1996 with active follow-up through 2005) comprising current and former heavy smokers were analyzed. CARET was a multicenter randomized, double-blind placebo-controlled chemoprevention trial testing daily supplementation of 30 mg β-carotene+25 000 IU retinyl palmitate for primary prevention of lung cancer. Prostate cancer was a secondary outcome. Nonaggressive disease was defined as Gleason less than 7 and stage I/II. Aggressive disease was primarily defined as at least Gleason 7 or stage III/IV, and secondarily by excluding Gleason 3+4 from the first definition. BMI was calculated from measured weight and height. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for cancer incidence between BMI categories. During follow-up, 883 men were diagnosed with prostate cancer. In the analysis of aggressive disease when Gleason 3+4 was excluded, men with a BMI of at least 35 kg/m had an increased rate of prostate cancer (HR: 1.80, 95% CI: 1.04-3.11, Ptrend=0.04) compared with men with BMI 18-24.9 kg/m. No other differences were seen in risk estimates for overall, nonaggressive or aggressive prostate cancer including all Gleason 7 cases, between BMI categories. Our results show an association between having a BMI of at least 35 kg/m and an increased risk of aggressive prostate cancer (not including Gleason 3+4 tumors), but do not support an association between BMI and risk of overall, aggressive disease including all Gleason 7, or nonaggressive prostate cancer within a population of current and former heavy smokers.

The Emerging Role of Adiponectin in Female Malignancies

Obesity, characterized by excess body weight, is now accepted as a hazardous health condition and an oncogenic factor. In different epidemiological studies obesity has been described as a risk factor in several malignancies. Some biological mechanisms that orchestrate obesity-cancer interaction have been discovered, although others are still not completely understood. The unbalanced secretion of biomolecules, called "adipokines", released by adipocytes strongly influences obesity-related cancer development. Among these adipokines, adiponectin exerts a critical role. Physiologically adiponectin governs glucose levels and lipid metabolism and is fundamental in the reproductive system. Low adiponectin circulating levels have been found in obese patients, in which its protective effects were lost. In this review, we summarize the epidemiological, in vivo and in vitro data in order to highlight how adiponectin may affect obesity-associated female cancers.

Blood glucose, glucose balance, and disease-specific survival after prostate cancer diagnosis in the Finnish Randomized Study of Screening for Prostate Cancer

INTRODUCTION

Diabetes mellitus has been linked with adverse prostate cancer (PCa) outcomes. However, role of hyperglycemia in PCa progression is unclear. We evaluated the link between hyperglycemia and PCa survival among Finnish PCa patients.

METHODS

The study cohort included 1770 men with data on fasting glucose and diagnosed with PCa within the Finnish Randomized Study of Screening for PCa in 1995-2009. Additionally, 1398 men had data on glycated hemoglobin (HbA1c). Information on fasting glucose and HbA1c measurements was obtained from the regional laboratory database. Antidiabetic medication use was obtained from the prescription database of the Social Insurance Institution (SII). Time-dependent Cox regression analysis was used to estimate hazard ratios (HRs) and 95% confidence intervals for PCa death among diabetic, impaired glucose tolerant, and normoglycemic men.

RESULTS

During median follow-up of 9.9 years after the diagnosis, 182 men died from PCa. After adjustment for tumor stage, Gleason grade, and PSA level at diagnosis, diabetic fasting glucose level after PCa diagnosis was associated with elevated risk of PCa death compared to normoglycemic men (HR 1.67 95% CI 1.18-2.36). The risk association was strongest among participants with localized cancer at diagnosis; HR 2.39, 95% CI 1.45-3.93. The risk elevation was observed for glucose measurements taken up to 5 years earlier. Diabetic glucose levels measured before the diagnosis were not associated with PCa death.

CONCLUSION

Our study cohort suggests an increased risk of PCa death in men with diabetic fasting blood glucose levels, supporting the role of hyperglycemia as a risk factor for PCa progression.

Mitochondrial biology and prostate cancer ethnic disparity

Prostate cancer remains the second most prevalent cancer in men. Its incidence, progression and mortality profiles vary significantly by race and ethnicity, with African-American men having the highest incidence rate and mortality rate in the world. Although these disparities can be partially explained by socioeconomic factors, the underlying molecular causes are complex and require careful research. A considerable amount of literature exists, supporting the association between mitochondrial health and the incidence, aggression and risk of prostate cancer. Genetic alterations in mitochondrial DNA are frequent in prostate cancer; therefore, the resulting mitochondrial dysfunction and metabolic dysregulation may contribute to or indicate oncogenesis. Many of the prominent features of cancer cells are also closely related to mitochondrial functions, such as resistance to apoptosis, excess reactive oxygen species production and altered oxidative phosphorylation. In addition, prostate cancer ethnic disparity is influenced by environmental and lifestyle factors, which involves differences in mitochondrial metabolism and retrograde signaling events.

In-Hospital Mortality and Post-Surgical Complications Among Cancer Patients with Metabolic Syndrome

BACKGROUND

Metabolic syndrome (MetS) is an important etiologic and prognostic factor for cancer, but few studies have assessed hospitalization outcomes among patients with both conditions.

METHODS

Data was obtained from the Healthcare Cost and Utilization project Nationwide Inpatient Sample (HCUP-NIS). Study variables were assessed using ICD-9 codes on adults aged 40 years and over admitted to a US hospital between 2007 and 2011 with primary diagnosis of either breast, colorectal, or prostate cancer. We examined in-hospital mortality, post-surgical complications, and discharge disposition among cancer patients with MetS and compared with non-MetS patients.

RESULTS

Hospitalized breast (OR: 0.31, 95% CI: 0.20-0.46), colorectal (OR: 0.41, 95% CI: 0.35-0.49), and prostate (OR: 0.28, 95% CI: 0.16-0.49) cancer patients with MetS had significantly reduced odds of in-hospital mortality. The odds of post-surgical complications among breast (OR: 1.20, 95% CI: 1.03-1.39) and prostate (OR: 1.22, 95% CI: 1.09-1.37) cancer patients with MetS were higher, but lower by 7% among colorectal cancer patients with MetS. Additionally, breast (OR: 1.21, 95% CI: 1.11-1.32) and colorectal (OR: 1.06, 95% CI: 1.01-1.11) cancer patients with MetS had significantly higher odds for discharge to a skilled nursing facility compared with those without MetS, but this was not statistically significant among prostate cancer patients.

CONCLUSIONS

Adverse health outcomes were significantly higher among hospitalized patients with a primary diagnosis of cancer and MetS. Future studies are needed to identify clinical strategies for detecting and managing patients with MetS to reduce the likelihood of poor inpatient outcomes.

No effect of unacylated ghrelin administration on subcutaneous PC3 xenograft growth or metabolic parameters in a Rag1-/- mouse model of metabolic dysfunction

Ghrelin is a peptide hormone which, when acylated, regulates appetite, energy balance and a range of other biological processes. Ghrelin predominately circulates in its unacylated form (unacylated ghrelin; UAG). UAG has a number of functions independent of acylated ghrelin, including modulation of metabolic parameters and cancer progression. UAG has also been postulated to antagonise some of the metabolic effects of acyl-ghrelin, including its effects on glucose and insulin regulation. In this study, Rag1-/- mice with high-fat diet-induced obesity and hyperinsulinaemia were subcutaneously implanted with PC3 prostate cancer xenografts to investigate the effect of UAG treatment on metabolic parameters and xenograft growth. Daily intraperitoneal injection of 100 μg/kg UAG had no effect on xenograft tumour growth in mice fed normal rodent chow or 23% high-fat diet. UAG significantly improved glucose tolerance in host Rag1-/- mice on a high-fat diet, but did not significantly improve other metabolic parameters. We propose that UAG is not likely to be an effective treatment for prostate cancer, with or without associated metabolic syndrome.

Clinical association of metabolic syndrome, C-reactive protein and testosterone levels with clinically significant prostate cancer

Recently, the influence that metabolic syndrome (MetS), hormonal alterations and inflammation might have on prostate cancer (PCa) risk has been a subject of controversial debate. Herein, we aimed to investigate the association between MetS‐components, C‐reactive protein (CRP) and testosterone levels, and the risk of clinically significant PCa (Sig‐PCa) at the time of prostate biopsy. For that, men scheduled for transrectal ultrasound guided biopsy of the prostate were studied. Clinical, laboratory parameters and criteria for MetS characterization just before the biopsy were collected. A total of 524 patients were analysed, being 195 (37.2%) subsequently diagnosed with PCa and 240 (45.8%) meet the diagnostic criteria for MetS. Among patients with PCa, MetS‐diagnosis was present in 94 (48.2%). Remarkably, a higher risk of Sig‐PCa was associated to MetS, greater number of MetS‐components and higher CRP levels (odds‐ratio: 1.83, 1.30 and 2.00, respectively; P < 0.05). Moreover, higher circulating CRP levels were also associated with a more aggressive Gleason score in PCa patients. Altogether, our data reveal a clear association between the presence of MetS, a greater number of MetS‐components or CRP levels >2.5 mg/L with an increased Sig‐PCa diagnosis and/or with aggressive features, suggesting that MetS and/or CRP levels might influence PCa pathophysiology.

Impact of metabolic syndrome on oncologic outcomes at radical prostatectomy

PURPOSE

The associations between metabolic syndrome (MetS) and prostate cancer (CaP) outcomes following radical prostatectomy (RP) are not clear. This study aims to understand the role of MetS in influencing oncological outcomes at RP.

MATERIALS AND METHODS

Patients who underwent RP for CaP at our institution from 2000 to 2010 were identified; MetS prior to RP was ascertained with a modified version of the IDF-AHA/NHLBI using ICD-9 codes. Histopathological outcomes included surgical margins, pathological stage, and Gleason score (GS) upgrading. Long-term outcomes included biochemical recurrence (BCR), local recurrence, systemic progression, and CaP-specific mortality. Multivariable adjusted logistic regression and Cox proportional hazards regression assessed the association between MetS status and histopathological and long-term outcomes, respectively.

RESULTS

Of 8,504 RP patients, 1,054 (12.4%) had MetS at the time of RP. MetS patients were older, had higher biopsy GS, but lower pre-op prostatic specific antigen (PSA), higher pathological GS, and larger prostate volume. Adjusted logistic regression suggested an association between MetS and positive margins (odds ratio [OR] = 1.22, P = 0.025) and GS upgrading (OR = 1.28, P = 0.002). There was evidence of an increased risk of local recurrence (hazard ratio [HR] = 1.33, P = 0.037) and CaP-specific mortality (HR = 1.58, P < 0.001) for MetS patients. There was no evidence to suggest an association with BCR or systemic progression.

CONCLUSION

Men with MetS are at higher risk of GS upgrade and positive surgical margins at surgery, local recurrence, and CaP-specific mortality. Pathological stage, BCR, and systemic progression were not associated with MetS. Our data may be useful in patients' counseling, especially when active surveillance is an option.

Association between Dietary Inflammatory Index and the Risk of Prostate Cancer: A Meta-Analysis

BACKGROUND

Diet is a known source of pro- and anti-inflammatory mediators, and inflammatory markers have been associated with mechanisms involved in prostate cancer initiation and progression. The Dietary Inflammatory Index (DII^®) is a tool to assist researchers in determining the inflammatory potential of diet. The aim of this study was to conduct a meta-analysis to assess the association between DII and prostate cancer.

METHODS

EMBASE and MEDLINE were searched from inception to February 2018, for relevant observational studies. The random effects model was used to calculate the overall relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

Data from five case-control and one cohort study were eligible for inclusion. The adjusted pooled RR of prostate cancer for the highest (the most pro-inflammatory diet) versus lowest (the most anti-inflammatory diet) DII categories was 1.74 (95% CI: 1.24-2.43). The analysis in the DII score as a continuous variable was also performed and the results showed that the risk of prostate cancer was 9% higher for each one-point increase in the score.

CONCLUSION

This meta-analysis suggests that promoting diets rich in anti-inflammatory food components (i.e., whole grains, fish, green vegetables, and fruits) should help in reducing preventing prostate cancer.

Association of IRS2 overexpression with disease progression in intrahepatic cholangiocarcinoma

Insulin receptor substrate 2 (IRS2) is a candidate driver oncogene frequently amplified in cancer and is positively associated with IRS2 expression. The overexpression of IRS2 has been suggested to promote tumor metastasis. However, its function in intrahepatic cholangiocarcinoma (iCCA) has not been investigated extensively. The present study examined 86 cases of iCCA to analyze IRS2 expression and its correlation with clinicopathological characteristics using immunohistochemical assays. Three stable cell lines overexpressing IRS2 were established. The mobility potential of cells was compared in the basal condition and following manipulation using cell migration and invasion assays. Epithelial-mesenchymal transition (EMT)-associated proteins were assessed by western blotting. IRS2 was overexpressed in 29 iCCA cases (33.7%) and was significantly more frequent in cases with large tumor size (P=0.033), classified as an advanced stage by the American Joint Committee on Cancer (P=0.046). In comparison with the control cells, the three IRS2-overexpressing iCCA cell lines exhibited a statistically significant increase in mobility potential. Expression analysis of EMT markers demonstrated decreased epithelial marker levels and increased mesenchymal marker levels in IRS2-overexpressing cells compared with their corresponding control cells. The results of the present study indicate that IRS2 overexpression is characterized by a large tumor size and advanced tumor stage in iCCA, and that it may increase tumor mobility potential by regulating EMT pathways. Therefore, it is a valuable predictive indicator of metastasis and may provide a novel direction for targeted therapy in iCCA.

The impact of transcription on metabolism in prostate and breast cancers

Metabolic dysregulation is regarded as an important driver in cancer development and progression. The impact of transcriptional changes on metabolism has been intensively studied in hormone-dependent cancers, and in particular, in prostate and breast cancer. These cancers have strong similarities in the function of important transcriptional drivers, such as the oestrogen and androgen receptors, at the level of dietary risk and epidemiology, genetics and therapeutically. In this review, we will focus on the function of these nuclear hormone receptors and their downstream impact on metabolism, with a particular focus on lipid metabolism. We go on to discuss how lipid metabolism remains dysregulated as the cancers progress. We conclude by discussing the opportunities that this presents for drug repurposing, imaging and the development and testing of new therapeutics and treatment combinations.

Bioconjugated, Single-Use Biosensor for the Detection of Biomarkers of Prostate Cancer

Prostate cancer is prevalent among cancers in men. A simple method for screening of reliable biomarkers is pivotal for early detection of prostate cancer.  Prostate-specific antigen (PSA) has been a commonly used biomarker for prostate cancer, in spite of its false-positive limitation. On the other hand, alpha-methylacyl-CoA racemase (AMACR), a metabolic enzyme, has been proven to be a highly expressed biomarker in prostate cancer cells. Therefore, a method or tool, which can detect either PSA or AMACR or both simply, cost effectively, and with high sensitivity and selectivity is desirable. We describe a novel bioconjugated, single-use biosensor capable of detecting both PSA and AMACR antigens in undiluted human serum. The preparation of the biosensor by the bioconjugation mechanism occurred within a day, which could be completed prior to actual testing. The effectiveness of the bioconjugation mechanism and the coverage of the electrode surface of the biosensor were experimentally assessed. Measurements of PSA and AMACR antigens and the specificity of the biosensor were carried out using differential pulse voltammetry. This biosensor was single-use and cost-effective and required a small quantity of test medium and relatively short preparation time, providing a very attractive biosensor for the detection of the biomarkers of prostate cancer.

Night work and prostate cancer risk: results from the EPICAP Study

Objective

To investigate the role of night work in prostate cancer based on data from the EPICAP Study.

Methods

EPICAP is a French population-based case-control study including 818 incident prostate cancer cases and 875 frequency-matched controls that have been interviewed face to face on several potential risk factors including lifetime occupational history. Detailed information on work schedules for each job (permanent or rotating night work, duration, total number of nights, length of the shift, number of consecutive nights) as well as sleep duration and chronotype, was gathered. Prostate cancer aggressiveness was assessed by Gleason Score.

Results

Night work was not associated with prostate cancer, whatever the aggressiveness of prostate cancer, while we observed an overall increased risk among men with an evening chronotype (OR=1.83, 95% CI 1.05 to 3.19). A long duration of at least 20 years of permanent night work was associated with aggressive prostate cancer (OR=1.76, 95% CI 1.13 to 2.75), even more pronounced in combination with a shift length >10 hours or ≥ 6 consecutive nights (OR=4.64, 95% CI 1.78 to 12.13; OR=2.43, 95% CI 1.32 to 4.47, respectively).

Conclusion

Overall, ever night work, either permanent or rotating, was not associated to prostate cancer. Nevertheless, our results suggest that a long duration of permanent night work in combination with a long shift length or at least six consecutive nights may be associated with prostate cancer, particularly with aggressive prostate cancer. Further studies are needed to confirm those findings.

Exogenous IL-6 induces mRNA splice variant MBD2_v2 to promote stemness in TP53 wild-type, African American PCa cells

African American men (AAM) are at higher risk of being diagnosed with prostate cancer (PCa) and are at higher risk of dying from the disease compared to European American men (EAM). We sought to better understand PCa molecular diversity that may be underlying these disparities. We performed RNA‐sequencing analysis on high‐grade PCa to identify genes showing differential tumor versus noncancer adjacent tissue expression patterns unique to AAM or EAM. We observed that interleukin‐6 (IL‐6) was upregulated in the nonmalignant adjacent tissue in AAM, but in EAM IL‐6 expression was higher in PCa tissue. Enrichment analysis identified that genes linked to the function of TP53 were overrepresented and downregulated in PCa tissue from AAM. These RNA‐sequencing results informed our subsequent investigation of a diverse PCa cell line panel. We observed that PCa cell lines that are TP53 wild‐type, which includes cell lines derived from AAM (MDA‐PCa‐2b and RC77T), did not express detectable IL‐6 mRNA. IL‐6 treatment of these cells downregulated wild‐type TP53 protein and induced mRNA and protein expression of the epigenetic reader methyl CpG binding domain protein 2 (MBD2), specifically the alternative mRNA splicing variant MBD2_v2. Further investigation validated that upregulation of this short isoform promotes self‐renewal and expansion of PCa cancer stem‐like cells (CSCs). In conclusion, this report contributes to characterizing gene expression patterns in high‐grade PCa and adjacent noncancer tissues from EAM and AAM. The results we describe here advance what is known about the biology associated with PCa race disparities and the molecular signaling of CSCs.

Latest Evidence on the Impact of Smoking, Sports, and Sexual Activity as Modifiable Lifestyle Risk Factors for Prostate Cancer Incidence, Recurrence, and Progression: A Systematic Review of the Literature by the European Association of Urology Section of Oncological Urology (ESOU)

CONTEXT

Smoking, sexual activity, and physical activity (PA) are discussed as modifiable lifestyle factors associated with prostate cancer (PCa) development and progression.

OBJECTIVE

To evaluate the available evidence concerning the association of smoking, sexual activity, and sports and exercise on PCa risk, treatment outcome, progression, and cancer-specific mortality.

EVIDENCE ACQUISITION

A systematic review of studies published between 2007 and 2017 using MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials, and Web of Science databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement criteria was conducted.

EVIDENCE SYNTHESIS

While data concerning the impact of smoking on PCa development remain conflicting, there is robust evidence that smoking is associated with aggressive tumor features and worse cancer-related outcome, which seems to be maintained for 10 yr after smoking cessation. Less convincing and limited evidence exists for the association of sexual activity with PCa risk. The findings related to PA and PCa support the inference that exercise might be a useful factor in the prevention of PCa and tumor progression, while it is not finally proved under which specific conditions PA might be protective against disease development.

CONCLUSIONS

Smoking is associated with aggressive tumor features and worse cancer-related prognosis; as this negative impact seems to be maintained for 10yr after smoking cessation, urologists should advise men to quit smoking latest at PCa diagnosis to improve their prognosis. As several studies indicate a positive impact of exercise on tumor development, progression, and treatment outcome, it is certainly reasonable to advocate an active lifestyle. Least convincing evidence is available for the interaction of sexual activity and PCa, and well-conducted and longitudinal studies are clearly necessary to evaluate whether the suggested associations between PCa risk and sexual behavior are real or spurious.

PATIENT SUMMARY

In this systematic review, we looked at the impact of smoking, sexual activity, and sports and exercise on prostate cancer risk and outcome after treatment. While the evidence for sexual activity is not overall clear, we found that smoking might lead to more aggressive cancers and result in worse treatment outcome. Physical activity might prevent prostate cancer and improve cancer-related outcomes as well. Hence, it is certainly reasonable to advocate an active lifestyle and advise men to quit smoking.