Inflammation, infection, and prostate cancer

Neutrophil-and-monocyte-to-lymphocyte ratio is positively associated with elevated prostate-specific antigen levels and high-risk prostate cancer: evidence from the NHANES (2003-2008)

Introduction

Prostate cancer (PCa) is a prevalent malignancy in men globally. The total prostate-specific antigen (TPSA) test is essential for PCa screening. The neutrophil-and-monocyte-to-lymphocyte ratio (NMLR) has emerged as a potential biomarker for various diseases, but its relationship with PCa and TPSA is yet to be studied. This research aims to explore the connection between NMLR and TPSA levels, as well as high-risk prostate cancer (HRPCa), utilizing data from the National Health and Nutrition Examination Survey (NHANES) spanning 2003 to 2008.

Methods

The study included 4,248 U.S. adult males. NMLR was calculated as the ratio of the combined counts of peripheral neutrophils and monocytes to the counts of peripheral lymphocytes. Weighted multiple linear and logistic regression models were used to analyze the relationship between NMLR, TPSA levels, and HRPCa.

Results

A significant positive association was found between elevated NMLR levels and increased TPSA (β = 0.35, 95% CI: 0.21-0.49), as well as higher odds of HRPCa (OR = 2.04, 95% CI: 1.55-2.68). Smooth curve fitting results indicate that there is a nonlinear positive correlation between NMLR and TPSA, as well as between NMLR and HRCa.

Conclusion

This study reveals a significant relationship between NMLR, TPSA levels, and HRPCa odds among U.S. males, suggesting that NMLR could be a valuable biomarker for assessing PCa risk, underscoring inflammation's role in prostate health. Further research is encouraged to explore its applications in early detection, treatment efficacy evaluation and risk stratification.

Oxidative Stress in Benign Prostatic Hyperplasia: Mechanisms, Clinical Relevance and Therapeutic Perspectives

BACKGROUND/OBJECTIVES

Benign prostatic hyperplasia (BPH) is among the most common conditions affecting men as they age, resulting in lower urinary tract symptoms (LUTS) that can profoundly impact quality of life. While historically attributed primarily to androgenic imbalances, current evidence implicates additional factors-particularly oxidative stress (OS) and chronic inflammation-in BPH pathogenesis. This review aims to synthesize research on the interplay between OS, inflammation, and hormonal regulation in BPH, emphasizing their clinical relevance and potential therapeutic implications.

METHODS

A comprehensive review of peer-reviewed literature was conducted focusing on mechanistic studies, clinical trials, and observational reports. Searches included data on ROS generation, antioxidant capacity, inflammatory mediators, and their contribution to pathological prostatic overgrowth. Potential interventions targeting OS-such as antioxidant supplementation, anti-inflammatory drugs, vitamin D receptor agonists, and phytotherapeutics-were also evaluated for their efficacy and safety profiles.

RESULTS

Chronic inflammation and OS were consistently identified within hyperplastic prostate tissue. Excessive ROS production, diminished antioxidant defense, and sustained cytokine release create a proproliferative and antiapoptotic environment, accelerating disease progression. Metabolic comorbidities (e.g., obesity, insulin resistance) further exacerbate these imbalances. Standard therapies (α-blockers and 5-ARIs) effectively relieve symptoms but do not directly address the oxidative-inflammatory axis. Emerging evidence suggests that pharmacological and dietary approaches targeting OS and inflammation may reduce prostate volume expansion and alleviate LUTS.

CONCLUSIONS

Findings indicate that OS and inflammation are key contributors to BPH progression. Incorporating antioxidant and anti-inflammatory strategies alongside conventional treatments holds promise for improving clinical outcomes and patient quality of life. Future research should focus on validating OS-specific biomarkers and optimizing personalized therapy regimens.

Comparison of serum uric acid levels between localised prostate cancer patients and a control group

AIM

The aim of this study is to find out whether serum uric acid levels in patients with localised prostate cancer differ from patients with lower urinary tract symptoms without carcinoma prostate.

MATERIAL AND METHODS

We performed a prospective observational study of 60 patients having age ⩾ 50 years with c/o lower urinary tract symptoms( LUTS) evaluated by digital rectal examination (DRE), prostate-specific antigen (PSA) level and ultrasonography kidney, ureter, bladder (USG KUB) prostate and patients who were suspicious for carcinoma prostate underwent trans rectal ultrasonography (TRUS) biopsy of prostate. Patients with biopsy s/o prostate cancer were evaluated for metastasis and localised cancer patients were considered as CASE group. Patients with negative biopsy and other patients having LUTS were considered as CONTROL group. The age, serum uric acid level, PSA value, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and white blood cell (WBC) count were measured. Serum uric acid level was compared in both the groups.

RESULTS

The mean serum uric acid level was lower in prostate cancer group (4.77 mg/dl) than control group (6.22 mg/dl) that was statistically significant (p < 0.001). The mean PSA value was 7.43 ng/dl in cancer group and 2.72 ng/dl in control group. (p < 0.001). The mean C-reactive protein (CRP) values were 1.32 and 0.45 respectively (p < 0.001), erythrocyte sedimentation rate (ESR) were found 21 and 10.5 respectively (p < 0.001)and total leucocyte counts (TLC) were found 6.450 and 5.120 respectively (p < 0.001). All were statistically significant (p < 0.05).

CONCLUSION

The serum uric acid levels measured in localised prostate cancer patients were found to be reduced compared to the control group and inflammatory markers were found to be increased. Decreased levels of serum uric acid and increased levels of inflammatory markers were determined as risk factors for prostate cancer.

Association between monocyte-to-lymphocyte ratio and prostate cancer in the U.S. population: a population-based study

Introduction

Monocyte-to-lymphocyte ratio (MLR) is a convenient and noninvasive inflammatory biomarker, and inflammation has been reported to be associated with prostate cancer (PCa). Our objective was to ascertain any possible correlation between PCa and MLR.

Methods

We utilized data from the 1999-2020 cycles of the National Health and Nutrition Examination Survey (NHANES) regarding MLR and PCa. The independent associations of MLR and other inflammatory biomarkers (platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), system inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI)) with PCa was investigated using weighted multivariate logistic regression and generalized additive models. Receiver operating characteristic (ROC) curves were conducted to evaluate and contrast their diagnostic capabilities.

Results

The analysis we conducted comprised 25,367 persons in total. The mean MLR was 0.31 ± 0.14. The prevalence of PCa was 3.1%. A positive association was found between MLR and PCa (OR = 2.28; 95% CI: 1.44, 3.62). According to the interaction tests, age, body mass index (BMI), hypertension, diabetes, and smoking status did not significantly impact the relationship between MLR and PCa (all p for interaction >0.05). ROC analysis showed that MLR had a stronger discriminative ability and accuracy in predicting PCa than other inflammatory biomarkers (NLR, SII, AISI, PLR, and SIRI).

Conclusion

MLR might be better than other inflammatory biomarkers (NLR, SIRI, AISI, PLR, and SII) in predicting PCa. American adults who have elevated levels of MLR, NLR, PLR, SII, and AISI should be aware that they have a greater risk of PCa.

Symptomatic Benign Prostatic Hyperplasia with Suppressed Epigenetic Regulator HOXB13 Shows a Lower Incidence of Prostate Cancer Development

Our objective was to identify variations in gene expression that could help elucidate the pathways for the development of prostate cancer (PCa) in men with Benign Prostatic Hyperplasia (BPH). We included 98 men with BPH, a positive prostate MRI (Prostate Imaging Reporting and Data System; PIRADS ≥ 4), and a negative biopsy from November 2014 to January 2018. RNA sequencing (RNA-Seq) was performed on tissue cores from the MRI lesion and a geographically distant region (two regions per patient). All patients were followed for at least three years to identify who went on to develop PCa. We compared the gene expressions of those who did not develop PCa ("BPH-only") vs. those who did ("BPH/PCa"). Then, we identified the subset of men with BPH who had the highest American Urological Association (AUA) symptom scores ("symptomatic BPH") and compared their gene expression to the BPH/PCa group. At a median follow-up of 47.5 months, 15 men had developed PCa while 83 did not. We compared gene expressions of 14 men with symptomatic BPH (AUAss ≥ 18) vs. 15 with BPH/PCa. We found two clusters of genes, suggesting the two groups had distinctive molecular features. Differential analysis revealed genes that were upregulated in BPH-only and downregulated in BPH/PCa, and vice versa. Symptomatic BPH men had upregulation of T-cell activation markers (TCR, CD3, ZAP70, IL-2 and IFN-γ and chemokine receptors, CXCL9/10) expression. In contrast, men with BPH/PCa had upregulation of NKX3-1 and HOXB13 transcription factors associated with luminal epithelial progenitors but depleted of immune cells, suggesting a cell-autonomous role in immune evasion. Symptomatic BPH with immune-enriched landscapes may support anti-tumor immunity. RNA sequencing of benign prostate biopsy tissue showing upregulation of NKX3-1 and HOXB13 with the absence of T-cells might help in identifying men at higher risk of future PCa development, which may be useful in determining ongoing PCa screening.

Role of microbiome and its metabolite, short chain fatty acid in prostate cancer

The microbiome which is an assembly of all microbes living inside our bodies performs a major role in maintaining human health and wellness. It has been found that the imbalance of the microbiome can cause various diseases in humans. Similarly, there is growing evidence that the microbiome largely affects a person's chance of contracting certain cancers and how the disease develops and progresses. Studies have shown that about 15% to 20% of all cancers are caused by microbial pathogens. The prevalence of prostate cancer, which is increasing rapidly in Korea, is related to lifestyle including diet. These diets can alter the gut microbial composition, and the effect of the microbiome on prostate cancer development can be estimated. However, the microbiome associated with prostate cancer has been reported differently according to race. This means that the metabolite rather than the specific microbiome will be important. Short chain fatty acids, metabolites of the microbiome, plays an important role in the action mechanism of the microbiome. Short chain fatty acids play roles such as immunomodulation and inhibition of histone deacetylase. Here, we examined the most up-to-date literature featuring the effects of the microbiome on the risk and pathogenesis of prostate cancer.

Molecular Landscape of LncRNAs in Prostate Cancer: A focus on pathways and therapeutic targets for intervention

Background

One of the most malignant tumors in men is prostate cancer that is still incurable due to its heterogenous and progressive natures. Genetic and epigenetic changes play significant roles in its development. The RNA molecules with more than 200 nucleotides in length are known as lncRNAs and these epigenetic factors do not encode protein. They regulate gene expression at transcriptional, post-transcriptional and epigenetic levels. LncRNAs play vital biological functions in cells and in pathological events, hence their expression undergoes dysregulation.

Aim of review

The role of epigenetic alterations in prostate cancer development are emphasized here. Therefore, lncRNAs were chosen for this purpose and their expression level and interaction with other signaling networks in prostate cancer progression were examined.

Key scientific concepts of review

The aberrant expression of lncRNAs in prostate cancer has been well-documented and progression rate of tumor cells are regulated via affecting STAT3, NF-κB, Wnt, PI3K/Akt and PTEN, among other molecular pathways. Furthermore, lncRNAs regulate radio-resistance and chemo-resistance features of prostate tumor cells. Overexpression of tumor-promoting lncRNAs such as HOXD-AS1 and CCAT1 can result in drug resistance. Besides, lncRNAs can induce immune evasion of prostate cancer via upregulating PD-1. Pharmacological compounds such as quercetin and curcumin have been applied for targeting lncRNAs. Furthermore, siRNA tool can reduce expression of lncRNAs thereby suppressing prostate cancer progression. Prognosis and diagnosis of prostate tumor at clinical course can be evaluated by lncRNAs. The expression level of exosomal lncRNAs such as lncRNA-p21 can be investigated in serum of prostate cancer patients as a reliable biomarker.

Bacteria-Mediated Oncogenesis and the Underlying Molecular Intricacies: What We Know So Far

Cancers are known to have multifactorial etiology. Certain bacteria and viruses are proven carcinogens. Lately, there has been in-depth research investigating carcinogenic capabilities of some bacteria. Reports indicate that chronic inflammation and harmful bacterial metabolites to be strong promoters of neoplasticity. Helicobacter pylori-induced gastric adenocarcinoma is the best illustration of the chronic inflammation paradigm of oncogenesis. Chronic inflammation, which produces excessive reactive oxygen species (ROS) is hypothesized to cause cancerous cell proliferation. Other possible bacteria-dependent mechanisms and virulence factors have also been suspected of playing a vital role in the bacteria-induced-cancer(s). Numerous attempts have been made to explore and establish the possible relationship between the two. With the growing concerns on anti-microbial resistance and over-dependence of mankind on antibiotics to treat bacterial infections, it must be deemed critical to understand and identify carcinogenic bacteria, to establish their role in causing cancer.

Predictive value of the monocyte-to-lymphocyte ratio in the diagnosis of prostate cancer

It has been reported that inflammation and immune system are related to prostate cancer. The neutrophil-to-lymphocyte ratio (NLR), as well as the platelet-to-lymphocyte ratio (PLR), have already been proposed as new indices to help diagnose prostate cancer (PCa). However, the monocyte-to-lymphocyte ratio (MLR) with regard to PCa has rarely been mentioned.To investigate the capability of the MLR to predict PCa.Patients who were pathologically diagnosed with PCa in our hospital and healthy control subjects who conformed to the inclusion criteria were enrolled. Patient data were recorded, including age, complete blood counts, blood biochemistry, and serum prostate-specific antigen (PSA) levels. The differences in these data between the groups were analyzed and the diagnostic value of the MLR was compared with PSA.Our study included a total of 100 patients with PCa and 103 healthy control subjects. Patients with PCa presented with a significantly higher NLR, MLR, and PLR compared to control subjects. However, the hemoglobin and lymphocyte levels were lower (P < .05) in PCa patients. The area under the curve (AUC) of PSA and ratio of free/total serum prostate-specific antigen were 0.899 (95% confidence interval [CI]: 0.857-0.942) and 0.872 (95% CI: 0.818-0.926), respectively, while the AUC of the MLR was 0.852 (95% CI: 0.798-0.906), which was higher than that of the NLR, PLR, and any other blood parameters. Additionally, the optimal cut-off value of the MLR for PCa was 0.264, with a specificity of 87.4% and a sensitivity of 72.0%. An evaluation of the diagnostic value of MLR + PSA gave an AUC of 0.936 (95% CI: 0.902-0.970). However, the AUC of MLR + PSA + f/tPSA was 0.996 (95% CI: 0.991-1.000). The diagnostic value of MLR + NLR + PSA gave an AUC of 0.945 (95% CI: 0.913-0.977), and the specificity is 0.971.PSA remains the most important diagnostic indicator. MLR combined with PSA and f/tPSA has the higher predictive value than PSA. It suggests that MLR may be another good predictive indicator of PCa. It can help reduce the clinical false positive rate.

Dissecting multiple roles of SUMOylation in prostate cancer

Protein modification with small ubiquitin-like modifiers (SUMOs) plays dual roles in prostate cancer (PCa) tumorigenesis and development. Any intermediary of the SUMO conjugation cycle going awry may forfeit the balance between tumorigenic potential and anticancer effects. Deregulated SUMOylation on the androgen receptor and oncoproteins also takes part in this pathological process, as exemplified by STAT3/NF-κB and tumor suppressors such as PTEN and p53. Here, we outline recent developments and discoveries of SUMOylation in PCa and present an overview of its multiple roles in PCa tumorigenesis/promotion and suppression, while elucidating its potential as a therapeutic target for PCa.

Human Prostate Epithelial Cells Activate the AIM2 Inflammasome upon Cellular Senescence: Role of POP3 Protein in Aging-Related Prostatic Inflammation

Increased levels of type I (T1) interferon (IFN)-inducible POP3 protein in myeloid cells inhibit activation of the AIM2 inflammasome and production of IL-1β and IL-18 proinflammatory cytokines. The AIM2 mRNA levels were significantly higher in benign prostate hyperplasia (BPH) than the normal prostate. Further, human normal prostate epithelial cells (PrECs), upon becoming senescent, activated an inflammasome. Because in aging related BPH senescent PrECs accumulate, we investigated the role of POP3 and AIM2 proteins in pre-senescent and senescent PrECs. Here we report that the basal levels of the POP3 mRNA and protein were lower in senescent (versus young or old) PrECs that exhibited activation of the T1 IFN response. Further, treatment of PrECs and a BPH cell line (BPH-1) that expresses the androgen receptor (AR) with the male sex hormone dihydrotestosterone (DHT) increased the basal levels of POP3 mRNA and protein, but not AIM2, and inhibited activation of the AIM2 inflammasome. Of interest, a stable knockdown of POP3 protein expression in the BPH-1 cell line increased cytosolic DNA-induced activation of AIM2 inflammasome. These observations suggest a potential role of POP3 protein in aging-related prostatic inflammation.

LncRNA LEF1-AS1 promotes metastasis of prostatic carcinoma via the Wnt/β-catenin pathway

BACKGROUND

Long noncoding RNAs (lncRNAs) are important functional regulators of many biological processes of cancers. However, the mechanisms by which lncRNAs modulate androgen-independent prostate cancer (AIPC) development remain largely unknown.

METHODS

Next-generation sequencing technology and RT-qPCR were used to assess LEF1-AS1 expression level in AIPC tissues and adjacent normal tissues. Functional in vitro experiments, including colony formation, EDU and transwell assays were performed to assess the role of LEF1-AS1 in AIPC. Xenograft assays were conducted to assess the effect of LEF1-AS1 on cell proliferation in vivo. Chromatin immunoprecipitation (ChIP) and RNA binding protein immunoprecipitation (RIP) assays were performed to elucidate the regulatory network of LEF1-AS1.

RESULTS

The next-generation sequencing results showed that LEF1-AS1 is significantly overexpressed in AIPC. Furthermore, our RT-qPCR assay data showed that LEF1-AS1 is overexpressed in AIPC tissues. Functional experiments showed that LEF1-AS1 promotes the proliferation, migration, invasion and angiogenic ability of AIPC cells in vitro and tumour growth in vivo by recruiting the transcription factor C-myb to the promoter of FZD2, inducing its transcription. Furthermore, LEF1-AS1 was shown to function as a competing endogenous RNA (ceRNA) that sponges miR-328 to activate CD44.

CONCLUSION

In summary, the results of our present study revealed that LEF1-AS1 acts as a tumour promoter in the progression of AIPC. Furthermore, the results revealed that LEF1-AS1 functions as a ceRNA and regulates Wnt/β-catenin pathway activity via FZD2 and CD44. Our results provide new insights into the mechanism that links the function of LEF1-AS1 with AIPC and suggests that LEF1-AS1 may serve as a novel potential target for the improvement of AIPC therapy.

Microbiome signatures in prostate cancer

We have established a microbiome signature for prostate cancer using an array-based metagenomic and capture-sequencing approach. A diverse microbiome signature (viral, bacterial, fungal and parasitic) was observed in the prostate cancer samples compared with benign prostate hyperplasia controls. Hierarchical clustering analysis identified three distinct prostate cancer-specific microbiome signatures. The three signatures correlated with different grades, stages and scores of the cancer. Thus, microbiome signature analysis potentially provides clinical diagnosis and outcome predictions. The array data were validated by PCR and targeted next-generation sequencing (NGS). Specific NGS data suggested that certain viral genomic sequences were inserted into the host somatic chromosomes of the prostate cancer samples. A randomly selected group of these was validated by direct PCR and sequencing. In addition, PCR validation of Helicobacter showed that Helicobacter cagA sequences integrated within specific chromosomes of prostate tumor cells. The viral and Helicobacter integrations are predicted to affect the expression of several cellular genes associated with oncogenic processes.

Epstein-Barr and BK virus in cancerous and noncancerous prostate tissue

Aim: We conducted a case–control study to examine the presence of BK virus (BKV) and Epstein barr virus (EBV) genome in prostate specimens of benign prostatic hyperplasia (BPH) and prostate cancer (PCa) in Iran. Materials & methods: 64 paraffin-embedded PCa specimens were included as case subjects and 57 paraffin-embedded BPH specimens as control. DNA extraction was carried out by phenol–chloroform technique and PCR for detection of BKV and EBV. Results: 90 (73%) out of 121 specimens were collected by prostatectomy and 31 (27%) by transurethral resection of the prostate. BKV was not detected in any of the samples and one positive EBV was reported. Conclusion: These findings provide further evidence against a causative role of BKV and EBV in the development of PCa.

Association between male accesory gland infections and prostate cancer in Turkish men: A case-control study

It is well known that chronic inflammation contributes to several forms of human cancer. Although several studies have investigated the association between prostatitis and prostate cancer, there is a lack of specifically designed study about male accessory gland infections (MAGI) and prostate cancer co-occurrence. We aimed to investigate this association with a case-control study in Turkish men. A total of 155 patients were enrolled to the study. After the pathological examination of the transrectal ultrasound-guided prostate biopsy specimens, patients were divided the two groups as control and prostate cancer and the presence of MAGI was determined. Of 155 patients, 145 met inclusion criteria. In the prostate cancer group, MAGI diagnose was determined in 18 of 31 patients (58.06%), while it was determined in 25 of 114 (21.93%) patients in the control group (p = .001). A significant correlation between MAGI and pathological Gleason score also revealed (p = .0001). We demonstrated that men with MAGI have increased risk for the development of prostate cancer. Moreover, in this population, most of the prostate cancers tend to be clinically significant or high grade.

Prognostic value of selected preoperative inflammation-based scores in patients with high-risk localized prostate cancer who underwent radical prostatectomy

Background

This study investigated the prognostic value of inflammation-based scores in patients with high-risk localized prostate cancer who underwent radical prostatectomy with or without neoadjuvant androgen deprivation therapy (ADT).

Methods

Inflammation-based scores included the neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), platelet-to-lymphocyte ratio (PLR), prognostic nutritional index (PNI), and plasma fibrinogen. A total of 440 patients (380 patients treated without neoadjuvant ADT and 60 patients treated with neoadjuvant ADT) were retrospectively evaluated in our medical center. Receiver operating characteristic (ROC) curves and Kaplan-Meier analyses were performed to compare the prognostic value of these scores. Univariate and multivariate Cox regression analyses were also performed.

Results

For all patients, dNLR and PNI were predictive of biochemical recurrence (.=0.041 and <0.001, respectively). Subgroup analysis of neoadjuvant strategies was also performed. For patients treated with neoadjuvant ADT, no selected inflammation-based scores were significantly correlated with biochemical recurrence (.>0.05). In contrast, for patients treated without neoadjuvant ADT, NLR (area under the ROC curve [AUC] =0.576, P=0.033), dNLR (.=0.585 and 0.017), PLR (AUC =0.582, P=0.024), and PNI (AUC =0.622, P<0.001) were predictive of biochemical recurrence. Kaplan-Meier analyses showed that dNLR (.=0.044), PLR (.=0.028), and PNI (.=0.004) were significantly associated with biochemical recurrence. Based on multivariable models, PNI was an independent predictor of biochemical recurrence (hazard ratio: 0.56, 95% confidence interval: 0.35-0.90, P=0.016).

Conclusion

High dNLR, high PLR, and low PNI were associated with poor biochemical recurrence-free survival in patients undergoing radical prostatectomy for high-risk localized prostate cancer not treated with neoadjuvant ADT. In particular, PNI was an independent prognostic factor for biochemical recurrence.

Cycloartane-type sapogenol derivatives inhibit NFκB activation as chemopreventive strategy for inflammation-induced prostate carcinogenesis

Chronic inflammation is associated to 25% of cancer cases according to epidemiological data. Therefore, inhibition of inflammation-induced carcinogenesis can be an efficient therapeutic approach for cancer chemoprevention in drug development studies. It is also determined that anti-inflammatory drugs reduce cancer incidence. Cell culture-based in vitro screening methods are used as a fast and efficient method to investigate the biological activities of the biomolecules. In addition, saponins are molecules that are isolated from natural sources and are known to have potential for tumor inhibition. Studies on the preparation of analogues of cycloartane-type sapogenols (9,19-cyclolanostanes) have so far been limited. Therefore we have decided to direct our efforts toward the exploration of new anti-tumor agents prepared from cycloastragenol and its production artifact astragenol. The semi-synthetic derivatives were prepared mainly by oxidation, condensation, alkylation, acylation, and elimination reactions. After preliminary studies, five sapogenol analogues, two of which were new compounds (2 and 3), were selected and screened for their inhibitory activity on cell viability and NFκB signaling pathway activity in LNCaP prostate cancer cells. We found that the astragenol derivatives 1 and 2 as well as cycloastragenol derivatives 3, 4, and 5 exhibited strong inhibitory activity on NFκB signaling leading the repression of NFκB transcriptional activation and suppressed cell proliferation. The results suggested that these molecules might have significant potential for chemoprevention of prostate carcinogenesis induced by inflammatory NFκB signaling pathway.

The effect of mast cells on the biological characteristics of prostate cancer cells

Aim of the study

To investigate the effects of mast cells on the proliferation, invasion, and metastasis of prostate cancer cells.

Material and methods

The mast cell P815 and prostate cancer LNCaP cells were chosen using a Transwell chamber to construct a two-cell cocultured in vitro model to observe the migration of mast cells to prostate cancer cells.

Results

In the migration experiment, the migration rate of mast cells from the experimental group (%) was 10.167 ±0.833, the mast cell migration rate (%) of the control group was 0.833 ±0.208, and the difference was statistically significant (p < 0.05). The MTT test showed that the OD value of cells in each group over time increased gradually, and 24 h after LNCaP cells were cocultured with different concentrations of mast cells, the OD value was significantly higher than that of the control group (p < 0.05). QRT-PCR and western blot results showed that, compared with the control group, E-cad expression from the experimental group was significantly weakened; N-cad and vimentin expression increased (p < 0.05), and c-kit and SCF expression from experimental group were significantly higher than that of the control group (p < 0.05). After the addition of c-kit neutralising antibodies, compared with the control group, the mast cell migration rate of experimental group decreased significantly and prostate cancer cell proliferation significantly decreased (p < 0.05).

Conclusions

Mast cells could promote the proliferation of prostate cancer cells and the occurrence of epithelial mesenchymal transition (EMT), which could promote the invasion and metastasis of prostate cancer cells.

SUMOylation of TBL1 and TBLR1 promotes androgen-independent prostate cancer cell growth

Chronic inflammation is strongly associated with prostate cancer pathogenesis. Transducin β-like protein (TBL1) and Transducin β-like 1X-linked receptor 1 (TBLR1) have been identified recently as a coactivator for NF-κB-mediated transcription; however, the underlying mechanism by which TBL1 and TBLR1 activate NF-κB function during inflammation remains unknown. Here, we demonstrate that cytokine production is significantly elevated in androgen-independent PC-3 prostate cancer cells compared with androgen-dependent LNCaP prostate cancer cells. Elevated cytokine production positively correlates with the TBL1 and TBLR1 SUMOylation level in PC-3 cells. We show that both TBL1 and TBLR1 are SUMOylated in response to TNF-α treatment, and this increases formation of the TBL1-TBLR1-NF-κB complex, which leads to NF-κB-mediated transcriptional activation of cytokine gene expression. Conversely, SENP1-mediated deSUMOylation of TBL1 and TBLR1 inhibits NF-κB-target gene expression by dissociating TBL1 and TBLR1 from the nuclear hormone receptor corepressor (NCoR) complex. TBL1 knockdown substantially suppresses inflammatory signaling and PC-3 cell proliferation. Collectively, these results suggest that targeted SUMOylation of TBL1 and TBLR1 may be a useful strategy for therapeutic treatment of androgen-independent prostate cancer.

Use of Non-steroidal Anti-inflammatory Drugs for Chemoprevention of Inflammation-induced Prostate Cancer

Objectives

Chronic inflammation has been known as one of the major causes of cancer progression and 25% of cancer cases initiate due to chronic inflammation according to epidemiologic data. It has been determined that chronic inflammation induces carcinogenesis through the abrogation of cell proliferation, apoptosis, and angiogenesis mechanisms. Therefore, it is believed that inhibition of inflammation-induced carcinogenic mechanisms is an efficient therapeutic strategy in drug development studies of cancer chemoprevention. It has also been observed that use of anti-inflammatory drugs reduces the incidence of cancer, and the risk of developing prostate cancer decreases 15-20% with regular use of aspirin and non-steroidal anti-inflammatory drugs (NSAID).

Materials and Methods

In this study, we investigated the effects of some clinically used NSAIDs on cellular mechanisms that play a role in inflammation-induced prostate carcinogenesis. Inhibition activities on the nuclear factor kappa-B signaling pathway, which activates tumorigenic mechanisms, as well as alterations on androgen receptor signaling, which regulates the proliferation of prostate cells, were investigated. In addition, protein kinase B (Akt) activation, which is stimulated a the inflammatory microenvironment, was examined.

Results

The results showed that anti-inflammatory agents alter the protein levels of androgen receptors as well as tumor suppressor NKX3.1, and might trigger an unexpected increase in Akt^(S473) level, which induces tumorigenesis.

Conclusion

It is suggested that inflammatory pathways and prostate carcinogenesis-specific mechanisms should be taken into account for the use of anti-inflammatory drugs for chemoprevention of inflammation-induced prostate cancer.

The mysterious relation between inflammation and prostate cancer

Recent studies showed that inflammation is a critical cause for initiation and/or development of many cancers. In prostate cancer (PC), the inflammatory cells usually populate an immune-competent organ. This inflammatory organ can be involved in the initiation and progression of PC. Here, we mainly focus on the role of inflammation in the PC and progression of castration-resistant PC (CRPC). Moreover, we summarize the roles of inflammation factors (such as chemokines and cytokines) in PC and CRPC. Taken together, this review gives an insight into therapy for PC and CRPC through anti-inflammation.

Prognostic value of inflammation in prostate cancer progression and response to therapeutic: a critical review

Prostate is an immune-competent organ normally populated by inflammatory cells. Prostatic inflammation origin can be multi-factorial and there are some emerging evidences on its possible role as a factor involved in prostate cancer (PC) pathogenesis and progression. This review critically analyzes the role of inflammation as a prognostic factor for progression and aggressiveness of PC. We verified the last 10 years literature data on the association between inflammation and PC aggressiveness, or PC response to therapies. Several studies tried to correlate different inflammatory factors with the aggressiveness and metastatization of PC; all data sustain the role of inflammation in PC progression but they also produce confusion to identify a reliable clinical prognostic marker. Data on patients submitted to radical prostatectomy (RP) showed that cases with marked intraprostatic tissue inflammation are associated with higher rate of biochemical progression; systemic inflammation markers appear to have a significant prognostic value. Analyzing data on patients submitted to radiotherapy (RT) emerges a significant association between high neuthrophil to lymphocyte ratio (NLR) and decreased progression free survival and overall survival; also plateled to lymphocyte ratio (PLR) and C-reactive protein (CRP) have been proposed as significant prognostic factors for progression and overall survival. In patients submitted to androgen deprivation therapy (ADT), inflammation may drive castration resistant PC (CRPC) development by activation of STAT3 in PC cells. NLR has been proposed as independent predictor of overall survival in CRPC submitted to chemotherapy. Most of data are focused on markers related to systemic inflammation such as NLR and CRP, more than specifically to chronic prostatic inflammation. The suggestion is that these inflammatory parameters, also if not specific for prostatic inflammation and possibly influenced by several factors other than PC, can integrate with established prognostic factors.

Immunogenicity of murine mPEG-red blood cells and the risk of anti-PEG antibodies in human blood donors

The immunocamouflage of non-ABO blood group antigens by membrane-grafted methoxypoly(ethylene glycol) (mPEG) may attenuate the risk of red blood cell (RBC) alloimmunization. However, concerns have been raised over the immunogenic risk of PEG and PEG-RBCs. To assess this risk, murine and human studies were performed. Mice were exposed to soluble PEG prior to, or between, multiple transfusions (∼60-day intervals) of control or mPEG-RBCs, and cell survival was determined by flow cytometry. In some studies, the control and mPEG-RBC groups were reversed after one or more transfusions. Furthermore, human blood donors and commercial intravenous immunoglobulin products were examined to detect anti-PEG antibodies and to assess the risk for false positives. Naïve mice receiving chronic mPEG-RBC transfusions had normal RBC survival curves with no evidence of anti-PEG antibodies. Similarly, challenge with soluble PEG did not elicit anti-PEG antibodies in mice. Studies in humans revealed no evidence of a high prevalence of anti-PEG antibodies in either blood donors or commercial intravenous immunoglobulin. However, by use of the methods employed by studies identifying high levels of anti-PEG antibodies, a significant level (∼15%) of "false positives" were detected in commercial antibodies of known (non-PEG) specificities. These findings suggest that methodologic problems yielded a high rate of false positives in these earlier studies. These data continue to support the clinical utility of cellular PEGylation and the low immunogenic risk of grafted mPEG.

Prostate chronic inflammation type IV and prostate cancer risk in patients undergoing first biopsy set: Results of a large cohort study

OBJECTIVE

In prostate specimens, chronic inflammatory infiltrate (CII) type IV has been detected, but its association with prostate cancer (PCa) is controversial. The aim of the present study is to investigate on associations of CII with PCa detection in patients undergoing prostate first biopsy set.

METHODS

Ultrasound transrectal-guided biopsies by the transperineal approach were retrospectively evaluated in 441 consecutive patients. The study excluded patients who were in active surveillance, prostate specific antigen (PSA) ≥30 ng/mL, re-biopsies, incidental PCa after transurethral resection of the prostate (TURP), less than 14 cores or metastatic. Analysis of population and subpopulations (with or without PCa) was performed by statistical methods which included Mann-Whitney (U test), Kruskal-Wallis test, Chi-squared statistic, logistic regression. Multivariate logistic regression models predicting mean probability of PCa detection were established.

RESULTS

PCa detection rate was 46.03%. Age, PSA, prostate volume (PV), prostate intraepithelial neoplasia (PIN) and CII were the significant independent predictors of PCa detection. PV (OR = 0.934) and CII (OR = 0.192) were both negative independent predictors. CII was a significant negative independent predictor in multivariate logistic regression models predicting the mean probability of PCa detection by age, PSA and PV. The inverse association of CII with PCa does not necessary mean protection because of PSA confounding.

CONCLUSION

In a population of patients undergoing prostate first biopsy set, CII was a strong negative independent predictor of PCa detection. CII type IV should be considered as an adjunctive parameter in re-biopsy or active surveillance protocols.

Gonorrhea and Prostate Cancer Incidence: An Updated Meta-Analysis of 21 Epidemiologic Studies

BACKGROUND

The association between gonorrhea and prostate cancer risk has been investigated widely, but the results remain inconsistent and contradictory. We conducted an updated meta-analysis to obtain a more precise estimate of this association.

MATERIAL AND METHODS

PubMed, EMBASE, and the Cochrane Library were searched for papers up to June 2014 to identify eligible studies. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the influence of gonorrhea on prostate cancer risk.

RESULTS

Twenty-one observational studies (19 case-control and 2 cohort) were eligible, comprising 9965 prostate cancer patients and 118 765 participants. Pooled results indicated that gonorrhea was significantly associated with increased incidence of prostate cancer (OR 1.31, 95% CI 1.14-1.52). The association between gonorrhea and prostate cancer was stronger in African American males (OR 1.32, 95% CI 1.06-1.65) than in Whites (OR 1.05, 95% CI 0.90-1.21).

CONCLUSIONS

Our findings suggest that gonorrhea is associated with an increased risk of prostate cancer, especially among African American males. These results warrant further well-designed, large-scale cohort studies to draw definitive conclusions.

Identification of Pathogen Signatures in Prostate Cancer Using RNA-seq

Infections of the prostate by bacteria, human papillomaviruses, polyomaviruses, xenotropic murine leukemia virus (MLV)-related gammaretroviruses, human cytomegaloviruses and other members of the herpesvirus family have been widely researched. However, many studies have yielded conflicting and controversial results. In this study, we systematically investigated the transcriptomes of human prostate samples for the unique genomic signatures of these pathogens using RNA-seq data from both western and Chinese patients. Human and nonhuman RNA-seq reads were mapped onto human and pathogen reference genomes respectively using alignment tools Bowtie and BLAT. Pathogen infections and integrations were analyzed in adherence with the standards from published studies. Among the nine pathogens (Propionibacterium acnes, HPV, HCMV, XMRV, BKV, JCV, SV40, EBV, and HBV) we analyzed, Propionibacterium acnes genes were detected in all prostate tumor samples and all adjacent samples, but not in prostate samples from healthy individuals. SV40, HCMV, EBV and low-risk HPVs transcripts were detected in one tumor sample and two adjacent samples from Chinese prostate cancer patients, but not in any samples of western prostate cancer patients; XMRV, BKV and JCV sequences were not identified in our work; HBV, as a negative control, was absent from any samples. Moreover, no pathogen integration was identified in our study. While further validation is required, our analysis provides evidence of Propionibacterium acnes infections in human prostate tumors. Noted differences in viral infections across ethnicity remain to be confirmed with other large prostate cancer data sets. The effects of bacterial and viral infections and their contributions to prostate cancer pathogenesis will require continuous research on associated pathogens.

Prevalence of prostatic calcification subtypes and association with prostate cancer

OBJECTIVE

To evaluate the prevalence and to classify prostatic calcification on transrectal ultrasonography (TRUS) and correlate the findings with histology.

METHODS

A prospective, blinded study of men undergoing TRUS and prostatic biopsy was designed. A standardized reproducible technique was used with a BK 7.5- to 12.5-MHz multiplanar probe. Representative images of the calcification in the sagittal and transverse planes were captured. Blind analysis by an experienced observer was performed. TRUS findings were categorized using a novel classification and correlated with histologic data.

RESULTS

A total of 274 patients (58.8%) had prostate cancer, 88 patients (18.9%) inflammation, and 104 patients (22.3%) had benign pathology. Interface calcification was present in 42.3% of patients. Peripheral or transitional zone calcification was unusual (6.8% and 9.0%, respectively). Of the peripheral zone calcification group patients, 78.1% had cancer on histology examination (P = .020).

CONCLUSION

Prevalence and characteristics of prostatic calcification have been described using this novel and practical classification. Although interface calcification is common and not associated with any particular pathology, peripheral zone calcification appears to be strongly associated with prostate cancer.

Androgens and androgen receptor signaling in prostate tumorigenesis

Androgens and androgen receptor (AR) signaling are necessary for prostate development and homeostasis. AR signaling also drives the growth of nearly all prostate cancer cells. The role of androgens and AR signaling has been well characterized in metastatic prostate cancer, where it has been shown that prostate cancer cells are exquisitely adept at maintaining functional AR signaling to drive cancer growth. As androgens and AR signaling are so intimately involved in prostate development and the proliferation of advanced prostate cancer, it stands to reason that androgens and AR are also involved in prostate cancer initiation and the early stages of cancer growth, yet little is known of this process. In this review, we summarize the current state of knowledge concerning the role of androgens and AR signaling in prostate tissue, from development to metastatic, castration-resistant prostate cancer, and use that information to suggest potential roles for androgens and AR in prostate cancer initiation.

Polymorphisms of an innate immune gene, toll-like receptor 4, and aggressive prostate cancer risk: a systematic review and meta-analysis

BACKGROUND

Toll-like receptor 4 (TLR4) is one of the best known TLR members expressed on the surface of several leukocytes and tissue cells and has a key function in detecting pathogen and danger-associated molecular patterns. The role of TLR4 in the pathophysiology of several age-related diseases is also well recognized, such as prostate cancer (PCa). TLR4 polymorphisms have been related to PCa risk, but the relationship between TLR4 genotypes and aggressive PCa risk has not been evaluated by any systematic reviews.

METHODS

We performed a systematic review and meta-analysis of candidate-gene and genome-wide association studies analyzing this relationship and included only white population. Considering appropriate criteria, only nine studies were analyzed in the meta-analysis, including 3,937 aggressive PCa and 7,382 controls.

RESULTS

Using random effects model, no significant association was found in the ten TLR4 SNPs reported by at least four included studies under any inheritance model (rs2737191, rs1927914, rs10759932, rs1927911, rs11536879, rs2149356, rs4986790, rs11536889, rs7873784, and rs1554973). Pooled estimates from another ten TLR4 SNPs reported by three studies also showed no significant association (rs10759930, rs10116253, rs11536869, rs5030717, rs4986791, rs11536897, rs1927906, rs913930, rs1927905, and rs7045953). Meta-regression revealed that study type was not a significant source of between-study heterogeneity.

CONCLUSIONS

TLR4 polymorphisms were not significantly associated with the risk of aggressive PCa.

PSGR promotes prostatic intraepithelial neoplasia and prostate cancer xenograft growth through NF-κB

Prostate-specific G-protein-coupled receptor (PSGR), a member of the olfactory subfamily of G-protein-coupled receptors, is specifically expressed in human prostate tissue and overexpressed in prostate cancer (PCa). This expression pattern suggests a possible role in PCa initiation and progression. We developed a PSGR transgenic mouse model driven by a probasin promoter and investigated the role of PSGR in prostate malignancy. Overexpression of PSGR induced a chronic inflammatory response that ultimately gave rise to premalignant mouse prostate intraepithelial neoplasia lesions in later stages of life. PSGR-overexpressing LnCaP cells in prostate xenografts formed larger tumors compared with normal LnCaP cancer cells, suggesting a role of PSGR in the promotion of tumor development. Furthermore, we identified nuclear factor-κB (NF-κB) or RELA as a key downstream target activated by PSGR signaling. We also show that this regulation was mediated in part by the phosphatidylinositol-3-kinase/Akt (PI3K/AKT) pathway, highlighting a collaborative role between PI3K/AKT and NF-κB during tumor inflammation downstream of PSGR in the initial phases of prostate disease.Oncogenesis (2014) 3, e114; doi:10.1038/oncsis.2014.29; published online 11 August 2014.

Pentraxin 3: a novel biomarker for predicting progression from prostatic inflammation to prostate cancer

Pentraxin-3 (PTX3) is a member of the pentraxin family of innate immune regulators, which includes C-reactive protein (CRP). PTX3 has been implicated in angiogenesis, proliferation, and immune escape in cancer. In the present study, we evaluated PTX3 tissue expression and serum concentration as a biomarker to discriminate prostatic inflammation and benign prostatic hyperplasia (BPH) from prostate cancer, and to determine whether PTX3 status may predict progression from BPH to prostate cancer. We analyzed 40 patients with biopsy-proven BPH who underwent a second prostate biopsy 12 to 36 months later when they were diagnosed with prostate cancer or inflammation/BPH (n = 20 patients each group). Furthermore, we evaluated PTX3 serum concentrations in an independent set of patients with biopsy-proven inflammation/BPH (n = 61) and prostate cancer (n = 56). We found reduced PTX3 tissue expression in patients with prostatic inflammation/BPH compared with patients who developed prostate cancer. In the latter group, there was an increase in PTX3 tissue expression between the first and second prostate biopsy. PTX3 serum levels were also higher in patients with prostate cancer than in patients with inflammation/BPH. In contrast, there was no difference in serum PSA or CRP levels in these two groups. ROC curve analysis confirmed the reliability of PTX3 serum levels in predicting prostate cancer development, identifying a cutoff value of 3.25 ng/mL with a sensitivity and a specificity of 89.3% and 88.5%, respectively. In summary, our results encourage further evaluation of PTX3 as a tissue biopsy and blood-borne biomarker to discriminate BPH from prostate cancer.

The same and not the same: heterogeneous functional activation of prostate tumor cells by TLR ligation

Background

Many types of tumors are organized in a hierarchy of heterogeneous cell populations with different molecular signature. Such heterogeneity may be associated with different responsiveness to microenvironment stimuli. In the present study, the effects of lipopolysaccharide (LPS) and lipoteichoic acid (LTA), as well-known mediators of inflammation, on cancerous behavior of three prostate tumor cells, LNCaP, PC3 and DU145, were investigated.

Methods

Expression of TLR1-10, CD14 and MyD88 transcripts was investigated by RT-PCR. Protein expression of TLR2 and 4 was scrutinized by flow cytometry, immunofluorescent staining and Western blotting. Experiments were set up to assess the effects of LPS and LTA at different concentrations and times on cell proliferation, extracellular matrix invasion, adhesion and cytokine production.

Results

We showed that prostate cancer cell lines differentially express TLR1-10, MyD88 and CD14 transcripts. DU145 failed to express TLR4 gene. Positively-identified TLR2 protein in all prostate cancer cells and TLR4 protein in PC3 and LNCaP by Western blotting was not accompanied by cell surface expression, as judged by flow cytometry. Immunofluorescent staining clearly demonstrated predominantly perinuclear localization of TLR2 and TLR4. LTA activation of all prostate cancer cells significantly increased cell proliferation. Regardless of lacking TLR4, DU145 cells proliferated in response to LPS treatment. While LPS caused increased invasiveness of LNCaP, invasive capacity of PC3 was significantly reduced after LPS or LTA stimulation. Stimulation of all prostate tumor cells with LTA was associated with increased cell adhesion and IL-8 production. IL-6 production, however, was differentially regulated by LPS stimulation in prostate tumor cells.

Conclusion

The data shows that cancer cells originated from the same histologically origin exhibit heterogeneous response to the same TLR ligand. Therefore, a thorough and comprehensive judgment on how and to what extent a particular cancer is affected by TLR agonist could not be inferred by studying an individual cell line.

Chlamydia trachomatis infection increases the expression of inflammatory tumorigenic cytokines and chemokines as well as components of the Toll-like receptor and NF-κB pathways in human prostate epithelial cells

Inflammation has been reported to play a major role in prostate carcinogenesis. Several bacterial infections can lead to prostate inflammation; however, until now, the precise molecular and cellular mechanisms linking inflammation to carcinogenesis have remained unclear. We therefore investigated the initiation of inflammation induced by Chlamydia trachomatis (C. trachomatis) infection in human prostate epithelial cells using an in vitro culture system in which human androgen-independent PC-3 prostate cancer epithelial cells were infected with C. trachomatis serovar L2. The expression levels of VEGF, ICAM-1, IL-6, IL-8, IL-1β, TNFα, CCL5, CCL2 and iNOS inflammation-related genes, as well as genes involved in the Toll-like receptor (TLR) pathway (TLR2, TLR4, CD14 and MyD88), were evaluated at the mRNA level in infected PC-3 cells 24 h after infection with C. trachomatis serovar L2. The expression levels of components of the NF-κB pathway (p65 and IκBα) were evaluated at the mRNA level in infected PC-3 cells at different time points (1, 6, 12 and 24 h) after infection. The expression levels of inflammation-related genes, components of the Toll-like receptor pathway and genes involved in NF-κB activation were analyzed in infected and uninfected cells using semi-quantitative RT-PCR. We detected a significant increase (p < 0.001) in inflammation-related cytokines in infected PC-3 cells. During infection, PC-3 cells elicited a proinflammatory response, as shown by NF-κB activation, TLR2 and TLR4 upregulation and the increased expression of inflammation-related genes. Furthermore, we observed significant upregulation of the adhesion molecules ICAM-1 and VEGF, which are two biomarkers correlated with tumor progression and immune system evasion. The present study suggests that human prostate cancer epithelial cells are susceptible to C. trachomatis infection and upregulate proinflammatory markers during infection.

The role of prostatic inflammation biomarkers in the diagnosis of prostate diseases

Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are chronic conditions, which are hormone-dependent and epidemiologically associated with prostate inflammation. As a large number of studies have demonstrated, the stimulation of T-cells at the level of prostatic chronic inflammatory infiltrates is followed by stromal and epithelial cell proliferation. The aim of this review is to present the actual level of knowledge in the field of prostatic immune response and chronic inflammation, and to analyze the relationships between chronic inflammation and BPH/PCa. The most studied prostatic inflammation biomarkers detected in biological fluids are also presented, together with their potential roles in the diagnosis and prognosis of prostatic disease.

Reduction of the CD16(-)CD56bright NK cell subset precedes NK cell dysfunction in prostate cancer

Background

Natural cytotoxicity, mediated by natural killer (NK) cells plays an important role in the inhibition and elimination of malignant tumor cells. To investigate the immunoregulatory role of NK cells and their potential as diagnostic markers, NK cell activity (NKA) was analyzed in prostate cancer (PCa) patients with particular focus on NK cell subset distribution.

Methods

Prospective data of NKA and NK cell subset distribution patterns were measured from 51 patients initially diagnosed with PCa and 54 healthy controls. NKA was represented by IFN-γ levels after stimulation of the peripheral blood with Promoca®. To determine the distribution of NK cell subsets, PBMCs were stained with fluorochrome-conjugated monoclonal antibodies. Then, CD16⁺CD56^dim and CD16⁻CD56^bright cells gated on CD56⁺CD3⁻ cells were analyzed using a flow-cytometer.

Results

NKA and the proportion of CD56^bright cells were significantly lower in PCa patients compared to controls (430.9 pg/ml vs. 975.2 pg/ml and 2.3% vs. 3.8%, respectively; p<0.001). Both tended to gradually decrease according to cancer stage progression (p for trend = 0.001). A significantly higher CD56^dim-to-CD56^bright cell ratio was observed in PCa patients (41.8 vs. 30.3; p<0.001) along with a gradual increase according to cancer stage progression (p for trend = 0.001), implying a significant reduction of CD56^bright cells in relation to the alteration of CD56^dim cells. The sensitivity and the specificity of NKA regarding PCa detection were 72% and 74%, respectively (best cut-off value at 530.9 pg/ml, AUC = 0.786).

Conclusions

Reduction of CD56^bright cells may precede NK cell dysfunction, leading to impaired cytotoxicity against PCa cells. These observations may explain one of the mechanisms behind NK cell dysfunction observed in PCa microenvironment and lend support to the development of future cancer immunotherapeutic strategies.

AIM2, an IFN-inducible cytosolic DNA sensor, in the development of benign prostate hyperplasia and prostate cancer

Close links have been noted between chronic inflammation of the prostate and the development of human prostatic diseases such as benign prostate hyperplasia (BPH) and prostate cancer. However, the molecular mechanisms that contribute to prostatic inflammation remain largely unexplored. Recent studies have indicated that the IFN-inducible AIM2 protein is a cytosolic DNA sensor in macrophages and keratinocytes. Upon sensing DNA, AIM2 recruits the adaptor ASC and pro-CASP1 to assemble the AIM2 inflammasome. Activation of the AIM2 inflammasome cleaves pro-interleukin (IL)-1β and pro-IL-18 and promotes the secretion of IL-1β and IL-18 proinflammatory cytokines. Given that human prostatic infections are associated with chronic inflammation, the development of BPH is associated with an accumulation of senescent cells with a proinflammatory phenotype, and the development of prostate cancer is associated with the loss of IFN signaling, the role of AIM2 in mediating the formation of prostatic diseases was investigated. It was determined that IFNs (α, β, or γ) induced AIM2 expression in human prostate epithelial cells and cytosolic DNA activated the AIM2 inflammasome. Steady-state levels of the AIM2 mRNA were higher in BPH than in normal prostate tissue. However, the levels of AIM2 mRNA were significantly lower in clinical tumor specimens. Accordingly, constitutive levels of AIM2 mRNA and protein were lower in a subset of prostate cancer cells as compared with BPH cells. Further, the cytosolic DNA activated the AIM2 inflammasome in the androgen receptor-negative PC3 prostate cancer cell line, suggesting that AIM2-mediated events are independent of androgen receptor status.

IMPLICATIONS

The AIM2 inflammasome has a fundamental role in the generation of human prostatic diseases.

A computational bioinformatics analysis of gene expression identifies candidate agents for prostate cancer

Prostate cancer is the second most frequently diagnosed cancer and the sixth leading cause of cancer death in males worldwide. Although great progress has been made, the molecular mechanisms of prostate cancer are far from being fully understood and treatment of this disease remains palliative. In this study, we sought to explore the molecular mechanism of prostate cancer and then identify biologically active small molecules capable of targeting prostate cancer using a computational bioinformatics analysis of gene expression. A total of 3068 genes, involved in cell communication, development, localisation and cell proliferation, were differentially expressed in prostate cancer samples compared with normal controls. Pathways associated with signal transduction, immune response and tumorigenesis were dysfunctional. Further, we identified a group of small molecules capable of reversing prostate cancer. These candidate agents may provide the groundwork for a combination therapy approach for prostate cancer. However, further evaluation for their potential use in the treatment of prostate cancer is still needed.

Effect of Serenoa repens (Permixon®) on the expression of inflammation-related genes: analysis in primary cell cultures of human prostate carcinoma

Background

To analyze the expression at basal level of inflammation-related cytokines and chemokines and the activation status of the NF-κB pathway, together with the proliferation and apoptosis indexes in two widely used in vitro tumor models, the androgen-dependent human Prostate Cancer (PC) cell line LNCaP and the androgen-independent PC3 , and in primary cultures of human PC cells. To assess in these models and primary cultures, the effects of Serenoa repens (LSESr, Permixon®) on proliferation/apoptosis ratio, inflammation-related genes expression and NF-κB pathway activation.

Methods

The expression of IL-6, CCL-5, CCL-2, COX-1, COX-2, iNOS inflammation-related genes has been evaluated at the mRNA level in two in vitro human PC models (LNCaP and PC3 cell lines) and in 40 independent human prostatic primary cultures obtained from PC patients undergoing radical prostatectomy. Tissue fragments were collected from both PC lesions and normal hyperplastic tissue counterparts for each case. All cultures were treated with two different amounts of Permixon® (44 and 88 μg/ml) for different time points (16, 24, 48 and 72 hours), depending on the cell type and the assay; the expression of inflammation-related genes, cell growth (proliferation/apoptosis ratio) and NF-κB activation has been analyzed in treated and untreated cells by means of semi-quantitative RNA-PCR, cell proliferation and immunofluorescence respectively.

Results

We detected a significant reduction (p <0.001) in PC and normal cells proliferation due to Permixon ® treatment. This result was related to an increase of the apoptotic activity showed by an increase in the number of anti-caspase-3 fluorescent cells. Almost all the inflammation-related genes (IL-6, CCL-5, CCL-2, COX-2 and iNOS) were expressed at the basal level in in vitro cultured cells and primary cultures and down-regulated by Permixon® treatment. This treatment interfered with NF-kB activation, detecting by the translocation of more than 30% of NF-κB p65 subunit to the nucleus.

Conclusions

The present study confirms the expression of inflammatory pattern in PC. We showed the effect of Permixon® on down-regulation of inflammatory-related genes in cell lines and in primary cultures. The inhibitory effect of Permixon® on cell growth could be partly associated to the down-regulation of inflammatory-related genes and to the activation of NF-κB pathway in prostate tissue.

The role of inflammatory mediators in the development of prostatic hyperplasia and prostate cancer

Benign prostatic hyperplasia and prostate cancer remain the most prevalent urologic health concerns affecting elderly men in their lifetime. Only 20% of benign prostatic hyperplasia and prostate cancer cases coexist in the same zone of the prostate and require a long time for initiation and progression. While the pathogenesis of both diseases is not fully understood, benign prostatic hyperplasia and prostate cancer are thought to have a multifactorial etiology, their incidence and prevalence are indeed affected by age and hormones, and they are associated with chronic prostatic inflammation. At least 20% of all human malignancies arise in a tissue microenvironment dominated by chronic or recurrent inflammation. In prostate malignancy, chronic inflammation is an extremely common histopathologic finding; its origin remains a subject of debate and may in fact be multifactorial. Emerging insights suggest that prostate epithelium damage potentially inflicted by multiple environmental factors such as infectious agents, dietary carcinogens, and hormones triggers procarcinogenic inflammatory processes and promotes cell transformation and disease development. Also, the coincidence of chronic inflammation and tumorigenesis in the peripheral zone has recently been linked by studies identifying so-called proliferative inflammatory atrophy as a possible precursor of prostatic intraepithelial neoplasia and prostate cancer. This paper will discuss the available evidence suggesting that chronic inflammation may be involved in the development and progression of chronic prostatic disease, although a direct causal role for chronic inflammation or infection in prostatic carcinogenesis has yet to be established in humans. Further basic and clinical research in the area, trying to understand the etiology of prostatic inflammation and its signaling pathway may help to identify new therapeutic targets and novel preventive strategies for reducing the risk of developing benign and malignant tumors of the prostate.

Short communication: RNASEL alleles and susceptibility to infection by human retroviruses and hepatitis viruses

RNASEL seems to function as an intracellular restriction factor blocking the establishment of infections caused by viral agents. Herein, we investigated whether allelic variants at the RNASEL gene might influence the susceptibility to viral infections or conditions potentially linked to viral agents. The allelic distribution at codon 462 was 139 (33.9%), 204 (49.8%), and 67 (16.3%) for RR, RQ, and QQ, respectively, in 410 individuals in Spain. There were no significant differences comparing 105 blood donors and 71 patients with HIV-1 infection, 27 with chronic hepatitis C, 67 with prostate cancer, and 107 with chronic fatigue syndrome. In contrast, two-thirds of 18 patients with HTLV-1 infection and 15 with chronic hepatitis B harbored RR. Thus, polymorphisms at the RNASEL gene do not seem to influence the susceptibility to common viral infections or conditions potentially of viral etiology. The role in influencing the susceptibility to HTLV-1 or HBV chronic infection warrants further examination in larger patient populations.

Can mycoplasma contribute to formation of prostate cancer?

PURPOSE

To reveal the possible role of mycoplasmas in the etiopathogenesis of prostate cancer.

METHODS

In the study, prostate biopsy was performed on 62 patients with an abnormal digital rectal examination and/or elevated PSA. The patients' age was between 62 and 77 (mean 65.4 years) years. Thirty-one patients had adenocarcinoma of the prostate histopathologically (group 1). From these patients, the specimens were divided into two subgroups as specimens with malignant findings (group 1A) and specimens with benign findings (group 1B). The control group consisted of 31 patients with benign prostatic hyperplasia (group 2). In the specimens, the presence of mycoplasma DNA was investigated by the polymerase chain reaction method.

RESULTS

The mycoplasma DNA was found to be positive in 11 (35.4 %) patients in group 1A and in 4 (12.9 %) patients in group 1B. There was no mycoplasma DNA in the patients in group 2. The differences between group 1A and group 1B, and between group 1A and group 2 were statistically significant (p values, respectively, 0.006 and 0.0001).

CONCLUSIONS

Our data supported the thesis that mycoplasma infections play a role in the etiopathogenesis of the prostate cancer.

Prostate cancer and inflammation: the evidence

Chronic inflammation is now known to contribute to several forms of human cancer, with an estimated 20% of adult cancers attributable to chronic inflammatory conditions caused by infectious agents, chronic non-infectious inflammatory diseases and/or other environmental factors. Indeed, chronic inflammation is now regarded as an 'enabling characteristic' of human cancer. The aim of this review is to summarize the current literature on the evidence for a role for chronic inflammation in prostate cancer aetiology, with a specific focus on recent advances regarding the following: (i) potential stimuli for prostatic inflammation; (ii) prostate cancer immunobiology; (iii) inflammatory pathways and cytokines in prostate cancer risk and development; (iv) proliferative inflammatory atrophy (PIA) as a risk factor lesion to prostate cancer development; and (v) the role of nutritional or other anti-inflammatory compounds in reducing prostate cancer risk.

Are repeat prostate biopsies safe? A cohort analysis from the SEARCH database

PURPOSE

Patients question whether multiple biopsy sessions cause worse prostate cancer outcomes. Therefore, we investigated whether there is an association between the number of prior biopsy sessions and biochemical recurrence after radical prostatectomy.

MATERIALS AND METHODS

Men in the SEARCH (Shared Equal Access Regional Cancer Hospital) database who underwent radical prostatectomy between 1988 and 2010 after a known number of prior biopsies were included in the analysis. Number of biopsy sessions (range 1 to 8) was examined as a continuous and categorical (1, 2 and 3 to 8) variable. Biochemical recurrence was defined as a prostate specific antigen greater than 0.2 ng/ml, 2 values at 0.2 ng/ml or secondary treatment for an increased prostate specific antigen. The association between number of prior biopsy sessions and biochemical recurrence was analyzed using the Cox proportional hazards model. Kaplan-Meier estimates of freedom from biochemical recurrence were compared among the groups.

RESULTS

Of the 2,739 men in the SEARCH database who met the inclusion criteria 2,251 (82%) had only 1 biopsy, 365(13%) had 2 biopsies and 123 (5%) had 3 or more biopsies. More biopsy sessions were associated with higher prostate specific antigen (p<0.001), greater prostate weight (p<0.001), lower biopsy Gleason sum (p=0.01) and more organ confined (pT2) disease (p=0.017). The Cox proportional hazards model demonstrated no association between number of biopsy sessions as a continuous or categorical variable and biochemical recurrence. Kaplan-Meier estimates of freedom from biochemical recurrence were similar across biopsy groups (log rank p=0.211).

CONCLUSIONS

Multiple biopsy sessions are not associated with an increased risk of biochemical recurrence in men undergoing radical prostatectomy. Multiple biopsy sessions appear to select for a low risk cohort.

Circumcision and the risk of prostate cancer

BACKGROUND

Several lines of evidence support a role for infectious agents in the development of prostate cancer (PCa). In particular, sexually transmitted infections (STIs) have been implicated in PCa etiology, and studies have found that the risk of acquiring a STI can be reduced with circumcision. Therefore, circumcision may reduce PCa risk.

METHODS

Participant data collected as part of 2 population-based case-control studies of PCa were analyzed. Self-reported circumcision status, age at circumcision, and age at first sexual intercourse were recorded along with a history of STIs or prostatitis. Multivariate logistic regression was used to estimate the relative risk of PCa by circumcision status.

RESULTS

Data from 1754 cases and 1645 controls were available. Circumcision before first sexual intercourse was associated with a 15% reduction in risk of PCa compared to that of uncircumcised men (95% confidence interval [CI], 0.73-0.99). This risk reduction was observed for cases with both less aggressive (odds ratio, 0.88; 95% CI, 0.74-1.04) and more aggressive (odds ratio, 0.82; 95% CI, 0.66-1.00) PCa features.

CONCLUSIONS

Circumcision before first sexual intercourse is associated with a reduction in the relative risk of PCa in this study population. These findings are consistent with research supporting the infectious/inflammation pathway in prostate carcinogenesis.