Inflammation in Benign Prostate Tissue and Prostate Cancer in the Finasteride Arm of the Prostate Cancer Prevention Trial

Benign prostatic hyperplasia nodules in patients treated with celecoxib and/or finasteride have reduced levels of NADH dehydrogenase [ubiquinone] iron-sulfur protein 3, a mitochondrial protein essential for efficient function of the electron transport chain

BACKGROUND

Benign prostatic hyperplasia (BPH) is a condition generally associated with advanced age in men that can be accompanied by bothersome lower urinary tract symptoms (LUTS) including intermittency, weak stream, straining, urgency, frequency, and incomplete bladder voiding. Pharmacotherapies for LUTS/BPH include alpha-blockers, which relax prostatic and urethral smooth muscle and 5ɑ-reductase inhibitors such as finasteride, which can block conversion of testosterone to dihydrotestosterone thereby reducing prostate volume. Celecoxib is a cyclooxygenase-2 inhibitor that reduces inflammation and has shown some promise in reducing prostatic inflammation and alleviating LUTS for some men with histological BPH. However, finasteride and celecoxib can reduce mitochondrial function in some contexts, potentially impacting their efficacy for alleviating BPH-associated LUTS.

METHODS

To determine the impact of these pharmacotherapies on mitochondrial function in prostate tissues, we performed immunostaining of mitochondrial Complex I (CI) protein NADH dehydrogenase [ubiquinone] iron-sulfur protein 3 (NDUFS3) and inflammatory cells on BPH specimens from patients naïve to treatment, or who were treated with celecoxib and/or finasteride for 28 days, as well as prostate tissues from male mice treated with celecoxib or vehicle control for 28 days. Quantification and statistical correlation analyses of immunostaining were performed.

RESULTS

NDUFS3 immunostaining was decreased in BPH compared to normal adjacent prostate. Patients treated with celecoxib and/or finasteride had significantly decreased NDUFS3 in both BPH and normal tissues, and no change in inflammatory cell infiltration compared to untreated patients. Mice treated with celecoxib also displayed a significant decrease in NDUFS3 immunostaining and no change in inflammatory cell infiltration.

CONCLUSIONS

These findings suggest that celecoxib and/or finasteride are associated with an overall decrease in NDUFS3 levels in prostate tissues but do not impact the presence of inflammatory cells, suggesting a decline in mitochondrial CI function in the absence of enhanced inflammation. Given that BPH has recently been associated with increased prostatic mitochondrial dysfunction, celecoxib and/or finasteride may exacerbate existing mitochondrial dysfunction in some BPH patients thereby potentially limiting their overall efficacy in providing metabolic stability and symptom relief.

Effects of a proprietary mixture of extracts from Sabal serrulata fruits and Urtica dioica roots (WS® 1541) on prostate hyperplasia and inflammation in rats and human cells

Introduction: Phytotherapeutics, particularly extracts from Sabal serrulata (saw palmetto) fruit or Urtica dioica (stinging nettle) root, are popular for the treatment of male lower urinary symptoms in many countries, but their mechanism of action is poorly understood. We performed in vivo and in vitro studies to obtain deeper insight into the mechanism of action of WS® 1541, a proprietary combination of a Sabal serrulata fruit and an Urtica dioica root extract (WS® 1473 and WS® 1031, respectively) and its components. Methods: We used the sulpiride model of benign prostatic hyperplasia in rats and tested three doses of WS® 1541 in comparison to finasteride, evaluating weight of prostate and its individual lobes as well as aspects of inflammation, oxidative stress, growth and hyperplasia. In human BPH-1 cells, we studied the effect of WS® 1473, WS® 1031, WS® 1541 and finasteride on apoptosis, cell cycle progression and migrative capacity of the cells. Results: WS® 1541 did not reduce prostate size in sulpiride treated rats but attenuated the sulpiride-induced changes in expression of most analyzed genes and of oxidized proteins and abrogated the epithelial thickening. In vitro, WS® 1473 and WS® 1031 showed distinct profiles of favorable effects in BPH-1 cells including anti-oxidative, anti-proliferative and pro-apoptotic effects, as well as inhibiting epithelial-mesenchymal-transition. Conclusion: This data supports a beneficial effect of the clinically used WS® 1541 for the treatment of lower urinary tract symptoms associated with mild to moderate benign prostate syndrome and provides a scientific rationale for the combination of its components WS® 1473 and WS® 1031.

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.

Exploring the Enigma of 5-ARIs Resistance in Benign Prostatic Hyperplasia: Paving the Path for Personalized Medicine

PURPOSE OF REVIEW

Despite the widespread utilization of 5-alpha reductase inhibitors (5-ARIs) for managing benign prostatic hyperplasia (BPH), certain BPH patients exhibit unresponsiveness to 5-ARIs therapy. This paper provides a comprehensive overview of the current perspectives on the mechanisms of 5-ARIs resistance in BPH patients and integrates potential biomarkers and underlying therapeutic options for 5-ARIs resistance. These findings may facilitate the development of novel or optimize more effective treatment options, and promote personalized medicine for BPH.

RECENT FINDINGS

The pathways contributing to resistance against 5-ARIs in certain BPH patients encompass epigenetic modifications, shifts in hormone levels, autophagic processes, and variations in androgen receptor structures, and these pathways may ultimately be attributed to inflammation. Promisingly, novel biomarkers, including intravesical prostatic protrusion, inflammatory factors, and single nucleotide polymorphisms, may offer predictive insights into the responsiveness to 5-ARIs therapy, empowering physicians to fine-tune treatment strategies. Additionally, on the horizon, GV1001 and mTOR inhibitors have emerged as potential alternative therapeutic modalities for addressing BPH in the future. After extensive investigation into BPH's pathological processes and molecular landscape, it is now recognized that diverse pathophysiological mechanisms may contribute to different BPH subtypes among individuals. This insight necessitates the adoption of personalized treatment strategies, moving beyond the prevailing one-size-fits-all paradigm centered around 5-ARIs. The imperative for early identification of individuals prone to treatment resistance will drive physicians to proactively stratify risk and adapt treatment tactics in future practice. This personalized medicine approach marks a progression from the current standard treatment model, emerging as the future trajectory in BPH management.

Role of Lipids and Lipid Metabolism in Prostate Cancer Progression and the Tumor’s Immune Environment

Modulation of lipid metabolism during cancer development and progression is one of the hallmarks of cancer in solid tumors; its importance in prostate cancer (PCa) has been demonstrated in numerous studies. Lipid metabolism is known to interact with androgen receptor signaling, an established driver of PCa progression and castration resistance. Similarly, immune cell infiltration into prostate tissue has been linked with the development and progression of PCa as well as with disturbances in lipid metabolism. Immuno-oncological drugs inhibit immune checkpoints to activate immune cells’ abilities to recognize and destroy cancer cells. These drugs have proved to be successful in treating some solid tumors, but in PCa their efficacy has been poor, with only a small minority of patients demonstrating a treatment response. In this review, we first describe the importance of lipid metabolism in PCa. Second, we collate current information on how modulation of lipid metabolism of cancer cells and the surrounding immune cells may impact the tumor’s immune responses which, in part, may explain the unimpressive results of immune-oncological treatments in PCa.

Testosterone does not affect lower urinary tract symptoms while improving markers of prostatitis in men with benign prostatic hyperplasia: a randomized clinical trial

PURPOSE

Benign Prostatic Hyperplasia (BPH) is a result of prostate inflammation, frequently occurring in metabolic syndrome (MetS). Low testosterone is common in MetS. A randomized clinical trial was designed to evaluate if 24 weeks of testosterone therapy (TTh) in BPH men with MetS and low testosterone improve urinary symptoms and prostate inflammation.

METHODS

One-hundred-twenty men with MetS waitlisted for BPH surgery were enrolled. They were categorized into normal testosterone (TT ≥ 12 nmol/L and cFT ≥ 225 pmol/L; n = 48) and testosterone deficient (TD) (TT < 12 nmol/L and/or cFT < 225 pmol/L; n = 72) then randomized to testosterone gel 2% (5 g/daily) or placebo for 24 weeks. At baseline and follow-up, questionnaires for urinary symptoms and trans-rectal ultrasound were performed. Prostate tissue was collected for molecular and histopathological analyses.

RESULTS

No differences in the improvement of urinary symptoms were found between TTh and placebo (OR [95% CI] 0.96 [0.39; 2.37]). In TD + TTh, increase in prostate but not adenoma volume was observed (2.64 mL [0.07; 5.20] and 1.82 mL [- 0.46; 0.41], respectively). Ultrasound markers of inflammation were improved. In a subset of 61 men, a hyper-expression of several pro-inflammatory genes was found in TD + placebo when compared with normal testosterone. TTh was able to counteract this effect. For 80 men, the inflammatory infiltrate was higher in TD + placebo than in normal testosterone (0.8 points [0.2; 1.4]) and TD + TTh men (0.9 points [0.2; 1.5]).

CONCLUSIONS

Twenty-four weeks of TTh in TD men with BPH and MetS improves ultrasound, molecular and histological proxies of prostate inflammation. This does not result in symptom improvement.

Identification of prostate cancer using multiparametric MR imaging characteristics of prostate tissues referenced to whole mount histopathology

In this study, the objective was to characterize the MR signatures of the various benign prostate tissues and to differentiate them from cancer. Data was from seventy prostate cancer patients who underwent multiparametric MRI (mpMRI) and subsequent prostatectomy. The scans included T2-weighted imaging (T2W), diffusion weighted imaging, dynamic contrast-enhanced MRI (DCE MRI), and MR spectroscopic imaging. Histopathology tissue information was translated to MRI images. The mpMRI parameters were characterized separately per zone and by tissue type. The tissues were ordered according to trends in tissue parameter means. The peripheral zone tissue order was cystic atrophy, high grade prostatic intraepithelial neoplasia (HGPIN), normal, atrophy, inflammation, and cancer. Decreasing values for tissue order were exhibited by ADC (1.8 10^-3 mm²/s to 1.2 10^-3 mm²/s) and T2W intensity (3447 to 2576). Increasing values occurred for DCE MRI peak (143% to 157%), DCE MRI slope (101%/min to 169%/min), fractional anisotropy (FA) (0.16 to 0.19), choline (7.2 to 12.2), and choline / citrate (0.3 to 0.9). The transition zone tissue order was cystic atrophy, mixed benign prostatic hyperplasia (BPH), normal, atrophy, inflammation, stroma, anterior fibromuscular stroma, and cancer. Decreasing values occurred for ADC (1.6 10^-3 mm²/s to 1.1 10^-3 mm²/s) and T2W intensity (2863 to 2001). Increasing values occurred for DCE MRI peak (143% to 150%), DCE MRI slope (101%/min to 137%/min), FA (0.18 to 0.25), choline (7.9 to 11.7), and choline / citrate (0.3 to 0.7). Logistic regression was used to create parameter model fits to differentiate cancer from benign prostate tissues. The fits achieved AUCs ≥0.91. This study quantified the mpMRI characteristics of benign prostate tissues and demonstrated the capability of mpMRI to discriminate among benign as well as cancer tissues, potentially aiding future discrimination of cancer from benign confounders.

Oral administration of berberine represses macrophage activation-associated benign prostatic hyperplasia: a pivotal involvement of the NF-κB

Benign prostatic hyperplasia (BPH) is one of the most common chronic diseases in men over the age of 50. Clinical studies have suggested that chronic inflammation is associated with BPH pathoprogression. Berberine (BB) is a natural compound found in Berberis vulgaris, Coptis chinensis and Phellodendron amurense. Although several studies have documented that BB may be effective for inflammation, the effects of the oral administration of BB on BPH are not fully understood. The effects of BB on chronic prostatic inflammation were evaluated in a testosterone-induced BPH animal model. Orally administered BB alleviated the pathological alterations induced by BPH and significantly suppressed the expression of inflammatory markers while enhancing the expression of antioxidant factors. Furthermore, BB regulated the activation of macrophages via NF-κB signaling pathway inhibition in the BPH rat model. The effects and underlying signaling pathway of BB in RWPE-1 cells exposed to macrophage conditioned medium (CM) were also demonstrated in vitro. While CM stimulation induced prostatic cell proliferation and upregulated the expression of inflammatory factors, BB exerted anti-proliferation and anti-inflammatory effects in RWPE-1 cells. These findings propose that BB suppresses androgen-dependent BPH development by targeting NF-κB-mediated pro-inflammatory signaling.

The Diagnostic Values of Pretreatment Serum Inflammation Markers and Lipoprotein in Men With Total Prostate-Specific Antigen Between 4 and 10 ng/ml

Background: The purpose of this study was to analyze the values of pretreatment serum inflammation markers, lipid, and lipoprotein for predicting the pathological results in men with total prostate-specific antigen between 4 and 10 ng/ml.

Materials and method: A total of 611 eligible patients diagnosed with total prostate-specific antigen between 4 and 10 ng/ml and who received a transrectal ultrasound-guided prostate biopsy between January 2014 and December 2019 were included in our study. All the patients were divided into groups according to their pathological results and we collected the data of their pretreatment indicators of the blood routine and biochemistry.

Results: The pathological results from prostate biopsies from 160 patients with prostate cancer and 451 patients with benign lesions. Age and total prostate-specific antigen values were significantly higher in patients with prostate cancer than those with benign lesions (P < 0.05). Red blood cell, platelet count, prealbumin, and triglyceride were significantly lower in patients with prostate cancer than those with benign lesions. Neutrophil–lymphocyte ratio, platelet–lymphocyte ratio, lymphocyte- monocyte ratio, and apolipoprotein B were lower and apolipoprotein A-I was higher in the prostate cancer group than in the benign lesions group but not significantly (P > 0.05). Multivariate logistic regression revealed that age and total prostate-specific antigen could be independent predictors for pathological results (OR, 1.064, 95%CI, 1.031–1.098, P < 0.001; OR, 1.232, 95%CI, 1.061–1.429, P = 0.006).

Conclusion: Higher age and total prostate-specific antigen were closely related to the pathological results. Prospective studies conducted with a large number of patients are needed to evaluate the diagnostic value of non-invasively pretreatment serum inflammation markers and lipoprotein for predicting the pathological results in men with total prostate-specific antigen between 4 and 10 ng/ml.

Review of the Roles and Interaction of Androgen and Inflammation in Benign Prostatic Hyperplasia

The lower urinary tract symptoms (LUTSs) and acute urinary retention (AUR) caused by benign prostatic hyperplasia (BPH) can seriously affect the quality of life of elderly men. Studies suggest that both androgens and inflammation greatly influence the occurrence and development of BPH in most patients. These two factors combined can also affect each other, leading to pathological changes in the stromal and epithelial tissue of the prostate transition zone in BPH patients. DHT in the prostate tissue of BPH patients may activate a chronic inflammatory response in the prostate, amplifying the expression of inflammatory factors and upregulating the proliferation ability of prostate tissue.

Testosterone, level of the lesion and age are independently associated with prostate volume in men with chronic spinal cord injury

PURPOSE

Although men with spinal cord injury (SCI) exhibit a prostate volume significantly smaller compared to age-matched able-bodied men, the independent association of lower prostate volume with its putative determinants has never been analyzed in this population. This study was designed to identify variables independently associated with prostate volume in men with chronic SCI.

METHODS

In this cross-sectional study, prostate volume of 138 men with chronic (> 1 years) SCI, aged 54.5 (25th-75th percentile: 36.0-66.0) years, was evaluated with trans-rectal ultrasonography. All patients underwent a complete neurological exam, as well as biochemical and hormonal assessment, including total testosterone (TT) levels. Free testosterone levels were calculated (cFT) by the Vermeulen formula.

RESULTS

The median prostate volume was 23.4 mL. At the univariate analysis, a larger prostate volume was associated with higher TT (p = 0.00001) and cFT (p = 0.001), SCI level below T12 (p = 0.007), more advanced age (p = 0.04), lower body mass index (p = 0.04), higher functional independence score (p = 0.06), higher values of prostate-specific antigen (p = 0.12) and shorter duration of the injury (p = 0.21). However, at the multiple regression analyses, an independent and positive association only persisted between the prostate volume with either TT or cFT levels, and, to a lesser extent, with age and a level of spinal lesion below T12. A prostate volume below the median value was observed in 91.4% (32/35) of patients with both androgen deficiency (TT < 264 ng/dL) and spinal lesion level ≥ T12, but only in 16.5% (2/12) of patients with both normal androgen levels and spinal lesion level below T12 (p < 0.001).

CONCLUSIONS

Our data indicate that lower testosterone levels and, to a lesser extent, a younger age and a spinal lesion level ≥ T12 represent the only variables exhibiting an independent association with a smaller prostate volume in men with SCI.

Current Knowledge of the Potential Links between Inflammation and Prostate Cancer

Inflammation is inherent in prostatic diseases and it is now accepted that it may facilitate cellular proliferation in both benign and malignant conditions. The strong relationship between prostatic inflammation and pathogenesis of benign prostatic hyperplasia (BPH) is supported by epidemiologic, histopathologic and molecular evidence. Contrariwise, the role of inflammation in prostate carcinogenesis is still controversial, although current data indicate that the inflammatory microenvironment can regulate prostate cancer (PCa) growth and progression. Knowledge of the complex molecular landscape associated with chronic inflammation in the context of PCa may lead to the introduction and optimization of novel targeted therapies. In this perspective, evaluation of the inflammatory component in prostate specimens could be included in routine pathology reports.

Combined Sabal and Urtica Extracts (WS® 1541) Exert Anti-proliferative and Anti-inflammatory Effects in a Mouse Model of Benign Prostate Hyperplasia

WS^® 1541 is a phytopharmaceutical drug combination containing a lipophilic extract from fruits of Sabal serrulata (WS^® 1473) and an aqueous ethanolic extract from roots of Urtica dioica (WS^® 1031). It is approved in several countries worldwide for the treatment of lower urinary tract syndrome (LUTS) linked to benign prostate hyperplasia (BPH). Clinical studies have demonstrated the efficacy of this unique combination in the treatment of BPH-related LUTS. However, its mechanisms of action in vivo remain partly uncharacterized. The aim of this study was to take advantage of a validated mouse model of BPH to better characterize its growth-inhibitory and anti-inflammatory properties. We used the probasin–prolactin (Pb-PRL) transgenic mouse model in which prostate-specific overexpression of PRL results in several features of the human disease including tissue hypertrophy, epithelial hyperplasia, increased stromal cellularity, inflammation, and LUTS. Six-month-old heterozygous Pb-PRL male mice were randomly distributed to five groups (11–12 animals/group) orally treated for 28 consecutive days with WS^® 1541 (300, 600, or 900 mg/kg/day), the 5α-reductase inhibitor finasteride used as reference (5 mg/kg/day) or vehicle (olive oil 5 ml/kg/day). Administration of WS^® 1541 was well tolerated and caused a dose-dependent reduction of prostate weight (vs. vehicle) that was statistically significant at the two highest doses. This effect was accompanied by a reduction in prostate cell proliferation as assessed by lower Ki-67 expression (qPCR and immunohistochemistry). In contrast, finasteride had no or only a mild effect on these parameters. The growth-inhibitory activity of WS^® 1541 was accompanied by a strong anti-inflammatory effect as evidenced by the reduced infiltration of cells expressing the leukocyte common antigen CD45. In sharp contrast, finasteride significantly increased the prostate inflammatory status according to this readout. Molecular profiling (qPCR) of 23 selected pro-inflammatory genes confirmed the strong anti-inflammatory potency of WS^® 1541 compared to finasteride. Since treatment of WS^® 1541 did not interfere with transgene expression and activity in the prostate of Pb-PRL mice, the effects observed in this study are entirely attributable to the intrinsic pharmacological action of the drug combination.

Testosterone and Benign Prostatic Hyperplasia

INTRODUCTION

Benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS) are frequent in aging. Nonetheless, their pathogenesis is largely unknown. The androgen dependence of the first phases of prostate development have inspired the historical view that higher testosterone (T) may be involved in BPH occurrence; however, recent evidence suggests a different scenario.

AIM

To review the available knowledge on the pathogenesis of BPH particularly concerning the role of T and the possible connections with metabolic impairments.

METHODS

Relevant records were retrieved by an extensive search in Medline, including the following keywords ("testosterone"[MeSH Terms] OR "testosterone"[All Fields]) AND ("prostatic hyperplasia"[MeSH Terms] OR ("prostatic"[All Fields] AND "hyperplasia"[All Fields]) OR "prostatic hyperplasia"[All Fields] OR ("benign"[All Fields] AND "prostatic"[All Fields] AND "hyperplasia"[All Fields]) OR "benign prostatic hyperplasia"[All Fields]). There were no limitations in terms of publication date or study design.

MAIN OUTCOME MEASURES

Preclinical and clinical studies have been reported, with special emphasis on our contribution and interpretation.

RESULTS

Inflammation is a key aspect of BPH development. Along with infectious agents, prostate inflammation can be triggered by metabolic stimuli, such as dyslipidemia, an important component of metabolic syndrome (MetS). Low T and hyperestrogenism frequently occur in MetS. Mounting evidence shows that low, rather than high, T and hyperestrogenism may favor prostate inflammation. Considering these data as a whole, we postulate that BPH is the result of the action of multiple factors, which reinforce their mutual detrimental effects.

CONCLUSION

T is not detrimental for the prostate, and treating hypogonadism could even produce relief from LUTS and limit prostatic inflammation, which generates and maintains the process leading to BPH. Rastrelli G, Vignozzi L, Corona G, et al. Testosterone and Benign Prostatic Hyperplasia. Sex Med Rev 2019;7:259-271.

Inverse Association of Prostatic Chronic Inflammation among Prostate Cancer Tumor Grade Groups: Retrospective Study of 738 Consecutive Cases Elected to a First Random Biopsy Set

OBJECTIVES

The study aimed to evaluate associations of prostatic chronic inflammation (PCI) with prostate cancer (PCA) grade groups by the International Society of Urological Pathology (ISUP).

METHODS

The study evaluated retrospectively 738 cases. The patient population was sampled into 3 groups collecting cases without and with PCA including subjects with lSUP grade group 1 and grade groups 2-5.

RESULTS

PCI was assessed in 185 patients (25.1%) and PCA in 361 patients (48.9%) of whom 188 (25.5%) had ISUP grade and 173 (23.4%) had ISUP groups 2-5 tumors. PCI inversely related to ISUP groups (p < 0.0001). In multivariate analysis, the risk of ISUP grade group 1 PCA compared to negative cases associated positively with age (OR 1.042; p = 0.001) but inversely with total prostate volume (TPV; OR 0.965; p < 0.0001) and PCI (OR 0.314; p < 0.0001). Intermediate-high grade tumors associated positively with age (OR 1.065; p < 0.0001), prostate specific antigen (OR 1.167; p < 0.0001), and abnormal digital rectal examination (OR 2.251; p < 0.0001) but inversely with TPV (OR 0.921; p < 0.0001) and PCI (OR 0.106; p < 0.0001).

CONCLUSIONS

PCI decreased the risk of PCA among ISUP tumor grade groups.

The role of prostatic inflammation in the development and progression of benign and malignant diseases

PURPOSE OF REVIEW

To evaluate the role of prostatic inflammation in the development and progression of benign and malignant prostatic diseases.

RECENT FINDINGS

Preclinical studies demonstrate that the activation of a chronic inflammatory prostatic response plays an important role in the pathogenesis and progression of benign prostatic hyperplasia (BPH) and prostate cancer (PCa). Approximately 40-70% of patients with BPH-related lower urinary tract symptoms harbour chronic inflammation at pathologic evaluation. These individuals should be considered at increased risk of symptom progression and acute urinary retention. Although currently available drugs approved for the treatment of BPH do not have an anti-inflammatory activity, the development of novel molecules that target the inflammatory pathway represents a promising area in the pharmacological treatment of BPH. Preclinical evidences support a potential role of chronic prostatic inflammation in the malignant transformation of prostatic cells. However, clinical investigations on the association between prostatic inflammation and the risk of PCa report conflicting results.

SUMMARY

Men with BPH-related lower urinary tract symptoms and chronic prostatic inflammation should be considered at increased risk of symptom progression and acute urinary retention during follow-up. Although preclinical studies provide a biological rationale for the relationship between inflammation and the risk of PCa, clinical investigations report conflicting results and the direct relationship between inflammation and malignant transformation in the human prostate is still debated.

Inflammation on Prostate Needle Biopsy is Associated with Lower Prostate Cancer Risk: A Meta-Analysis

PURPOSE

We performed a comprehensive literature review and meta-analysis to evaluate the association of inflammation on prostate needle biopsies and prostate cancer risk.

MATERIALS AND METHODS

We searched Embase®, PubMed® and Web of Science™ from January 1, 1990 to October 1, 2016 for abstracts containing the key words prostate cancer, inflammation and biopsy. Study inclusion criteria were original research, adult human subjects, cohort or case-control study design, histological inflammation on prostate needle biopsy and prostate cancer on histology. Two independent teams reviewed abstracts and extracted data from the selected manuscripts. Combined ORs and 95% CIs of any, acute and chronic inflammation were calculated using the random effects method.

RESULTS

Of the 1,030 retrieved abstracts 46 underwent full text review and 25 were included in the final analysis, comprising a total of 20,585 subjects and 6,641 patients with prostate cancer. There was significant heterogeneity among studies (I² = 84.4%, p <0.001). The presence of any inflammation was significantly associated with a lower prostate cancer risk in 25 studies (OR 0.455, 95% CI 0.337-0.573). There was no evidence of publication bias (p >0.05). When subanalyzed by inflammation type, acute inflammation in 4 studies and chronic inflammation in 15 were each associated with a lower prostate cancer risk (OR 0.681, 95% CI 0.450-0.913 and OR 0.499, 95% CI 0.334-0.665, respectively).

CONCLUSIONS

In a meta-analysis of 25 studies inflammation on prostate needle biopsy was associated with a lower prostate cancer risk. Clinically the presence of inflammation on prostate needle biopsy may lower the risk of a subsequent prostate cancer diagnosis.

A Prospective Study of Chronic Inflammation in Benign Prostate Tissue and Risk of Prostate Cancer: Linked PCPT and SELECT Cohorts

Background: We leveraged two trials to test the hypothesis of an inflammation-prostate cancer link prospectively in men without indication for biopsy.Methods: Prostate Cancer Prevention Trial (PCPT) participants who had an end-of-study biopsy performed per protocol that was negative for cancer and who subsequently enrolled in the Selenium and Vitamin E Cancer Prevention Trial (SELECT) were eligible. We selected all 100 cases and sampled 200 frequency-matched controls and used PCPT end-of-study biopsies as "baseline." Five men with PSA > 4 ng/mL at end-of-study biopsy were excluded. Tissue was located for 92 cases and 193 controls. We visually assessed inflammation in benign tissue. We estimated ORs and 95% confidence intervals (CI) using logistic regression adjusting for age and race.Results: Mean time between biopsy and diagnosis was 5.9 years. In men previously in the PCPT placebo arm, 78.1% of cases (N = 41) and 68.2% of controls (N = 85) had at least one baseline biopsy core (∼5 evaluated per man) with inflammation. The odds of prostate cancer (N = 41 cases) appeared to increase with increasing mean percentage of tissue area with inflammation, a trend that was statistically significant for Gleason sum <4+3 disease (N = 31 cases; vs. 0%, >0-<1.8% OR = 1.70, 1.8-<5.0% OR = 2.39, ≥5% OR = 3.31, P_trend = 0.047). In men previously in the finasteride arm, prevalence of inflammation did not differ between cases (76.5%; N = 51) and controls (75.0%; N = 108).Conclusions: Benign tissue inflammation was positively associated with prostate cancer.Impact: This first prospective study of men without biopsy indication supports the hypothesis that inflammation influences prostate cancer development. Cancer Epidemiol Biomarkers Prev; 26(10); 1549-57. ©2017 AACR.

Association between variants in genes involved in the immune response and prostate cancer risk in men randomized to the finasteride arm in the Prostate Cancer Prevention Trial

BACKGROUND

We reported that some, but not all single nucleotide polymorphisms (SNPs) in select immune response genes are associated with prostate cancer, but not individually with the prevalence of intraprostatic inflammation in the Prostate Cancer Prevention Trial (PCPT) placebo arm. Here, we investigated whether these same SNPs are associated with risk of lower- and higher-grade prostate cancer in men randomized to finasteride, and with prevalence of intraprostatic inflammation among controls. Methods A total of 16 candidate SNPs in IL1β, IL2, IL4, IL6, IL8, IL10, IL12(p40), IFNG, MSR1, RNASEL, TLR4, and TNFA and 7 tagSNPs in IL10 were genotyped in 625 white prostate cancer cases, and 532 white controls negative for cancer on an end-of-study biopsy nested in the PCPT finasteride arm. We used logistic regression to estimate log-additive odds ratios (OR) and 95% confidence intervals (CI) adjusting for age and family history.

RESULTS

Minor alleles of rs2243250 (T) in IL4 (OR = 1.46, 95% CI 1.03-2.08, P-trend = 0.03), rs1800896 (G) in IL10 (OR = 0.77, 95% CI 0.61-0.96, P-trend = 0.02), rs2430561 (A) in IFNG (OR = 1.33, 95% CI 1.02-1.74; P-trend = 0.04), rs3747531 (C) in MSR1 (OR = 0.55, 95% CI 0.32-0.95; P-trend = 0.03), and possibly rs4073 (A) in IL8 (OR = 0.81, 95% CI 0.64-1.01, P-trend = 0.06) were associated with higher- (Gleason 7-10; N = 222), but not lower- (Gleason 2-6; N = 380) grade prostate cancer. In men with low PSA (<2 ng/mL), these higher-grade disease associations were attenuated and/or no longer significant, whereas associations with higher-grade disease were apparent for minor alleles of rs1800795 (C: OR = 0.70, 95% CI 0.51-0.94, P-trend = 0.02) and rs1800797 (A: OR = 0.72, 95% CI 0.53-0.98, P-trend = 0.04) in IL6. While some IL10 tagSNPs were associated with lower- and higher-grade prostate cancer, distributions of IL10 haplotypes did not differ, except possibly between higher-grade cases and controls among those with low PSA (P = 0.07). We did not observe an association between the studied SNPs and intraprostatic inflammation in the controls.

CONCLUSION

In the PCPT finasteride arm, variation in genes involved in the immune response, including possibly IL8 and IL10 as in the placebo arm, may be associated with prostate cancer, especially higher-grade disease, but not with intraprostatic inflammation. We cannot rule out PSA-associated detection bias or chance due to multiple testing.