Clinical analysis of transurethral holmium laser enucleation in the treatment of benign prostatic hyperplasia with prostatic inflammation: A prospective research study

Objective

To investigate the clinical efficacy of holmium laser enucleation of the prostate (HoLEP) in the treatment of benign prostatic hyperplasia (BPH) with prostatic inflammation (PI).

Methods

We prospectively collected and followed up data on patients with BPH who underwent HoLEP at the Affiliated Hospital of Weifang Medical University between July 2021 and July 2022. According to the postoperative pathological results, the patients were divided into two groups: BPH without PI group (BPH group) and BPH with PI group. Statistical analysis was performed on clinical data, including age and body mass index (BMI), prostate volume (PV), postoperative residual urine volume (PVR), preoperative serum total prostate-specific antigen (tPSA), serum-free prostate-specific antigen (fPSA), preoperative and postoperative maximum urinary flow rate (Qmax), International Prostate Symptom Score (IPSS) before and 3 months after surgery, quality of life index (QoL) before and 3 months after surgery, and postoperative complications.

Results

A total of 41 patients were included in this study, including 16 in the BPH group and 25 in the BPH with PI group. There were no significant differences in preoperative age, BMI, PV, PVR, tPSA, fPSA, and f/tPSA between the BPH and BPH with PI groups (P > 0.05). The preoperative mean Qmax of the BPH and BPH with PI groups were 9.44 ± 2.449 and 7.52 ± 2.946 [mean ± standard deviation (SD)] ml/s, mean IPSS were 17.75 ± 5.335 and 24.24 ± 5.861 (mean ± SD), and mean QoL were 4.13 ± 0.806 and 4.48 ± 0.8 (mean ± SD), respectively. The postoperative mean Qmax of the BPH and BPH with PI groups were 20.38 ± 4.787 and 14.32 ± 3.827 (mean ± SD) ml/s, mean IPSS were 2.69 ± 1.25 and 5.84 ± 3.579 (mean ± SD), and mean QoL were 0.13 ± 0.342 and 0.92 ± 0.759 (mean ± SD), respectively. In both groups, Qmax significantly increased (P < 0.05) and IPSS and QoL significantly decreased after HoLEP (P < 0.05). Before and after surgery, the Qmax in the BPH with PI group was lower than that in the BPH group, and the IPSS and QoL levels in the BPH with PI group were higher than those in the BPH group (P < 0.05). Compared with the BPH group, the increase in Qmax in the BPH with PI group was smaller and the decrease in IPSS was larger (P < 0.05), but the variation in QoL was not statistically significant (P > 0.05).

Conclusion

Improvements in Qmax, IPSS, and QoL in BPH patients with PI after HoLEP surgery were lower than those in BPH patients alone. PI may be a predictor of a worse response to surgical treatment. However, more multicenter randomized controlled trials with larger samples and long-term follow-up are needed to verify this.

Bioptic prostatic inflammation correlates with false positive rates of multiparametric magnetic resonance imaging in detecting clinically significant prostate cancer

Introduction

The aim of this article was to determine the impact of bioptic prostatic inflammation (PI) on the false positive rate of multiparametric magnetic resonance imaging (mp-MRI) in detecting clinically significant prostate ancer (csPCa).

Material and methods

Our prostate biopsy database was queried to identify patients who underwent mp-MRI before PB at our institution. A dedicated uropathologist prospectively assessed bioptic PI using the Irani scores. We evaluated the association between mp-MRI findings, bioptic Gleason grade (GG) and aggressiveness of PI, and PCa detection.

Results

In total, 366 men were included. In patients with Prostate Imaging Reporting and Data System (PIRADS) 4-5 lesions, the csPCa (GG ≥2) rate was significantly higher in those with low-grade than in those with high-grade PI (36% vs 29.7%; p = 0.002), and in those with low-aggressive than in those with high-aggressive PI (37.7% vs 30.1%; p = 0.0003). The false positive rates of PIRADS 4–5 lesions for any PCa were 34.2% and 57.8% for low- and high-grade PI, respectively (p = 0.002); similarly, they were 29.5% and 59.4% for mildly and highly-aggressive PI (p = 0.0003). Potential study limitations include its retrospective analysis and single-center study and lack of assessment of the type of PI.

Conclusions

Bioptic PI directly correlates with false positive rates of mp-MRI in detecting csPCa. Clinicians should be aware that PI remains the most common pitfall of mp-MRI.

E-cadherin expression is inversely correlated with aging and inflammation in the prostate

INTRODUCTION AND OBJECTIVE

Benign prostatic hyperplasia (BPH) is a prostatic disease that is significantly associated with aging. However, it is not well understood how aging contributes to BPH pathogenesis. Several factors associated with an increased risk of BPH are also associated with increasing age, including chronic inflammation and declining epithelial barrier function. Thus, this study explored the potential associations between aging, loss of adherens junction protein E-cadherin and the presence of inflammatory mediators in prostate tissue specimens from healthy young donor and BPH patients.

METHODS

Serial prostate sections from a cohort of five donors aged 15-26 years and 13 BPH patients aged 50-77 years were immunostained with E-cadherin, COX-2, CD4, CD8, CD20 and CD68. E-cadherin and COX-2 H-Scores and the number of inflammatory cells were calculated for the same area in donor, normal adjacent prostate to BPH (NAP) and BPH specimens. Quantification and statistical correlation analyses were performed for comparisons between groups.

RESULTS

E-cadherin was decreased in aged NAP tissues and in BPH compared to young donor tissue. E-cadherin was inversely correlated with age and infiltration of inflammatory cells in NAP compared to young healthy donor prostate. Stromal COX-2 was positively correlated with age and inflammation. E-cadherin was further down-regulated in BPH, while COX-2 H-Scores were not significantly altered in BPH compared to NAP.

CONCLUSIONS

These findings suggest that aging is associated with down-regulation of E-cadherin and up-regulation of stromal COX-2 immunostaining in the prostate. E-cadherin immunostaining was inversely associated with age and inflammation, while stromal COX-2 immunostaining was positively associated with age and inflammation in the prostate. These findings suggest that the prostate epithelial barrier is altered and inflammation is increased with age in the prostate. These changes are further exacerbated in BPH, and may be involved in BPH pathogenesis.

Prostate-Specific Deletion of Cdh1 Induces Murine Prostatic Inflammation and Bladder Overactivity

Benign prostatic hyperplasia (BPH) is an age-related debilitating prostatic disease that is frequently associated with prostatic inflammation and bothersome lower urinary tract symptoms (LUTS). Animal models have shown that formalin- and bacterial-induced prostatic inflammation can induce bladder dysfunction; however, the underlying mechanisms contributing to prostatic inflammation in BPH and bladder dysfunction are not clear. We previously reported that E-cadherin expression in BPH is downregulated in hyperplastic nodules compared with expression in adjacent normal tissues. Here, we explored the potential consequences of prostatic E-cadherin downregulation on the prostate and bladder in vivo using an inducible murine model of prostate luminal epithelial-specific deletion of Cdh1. The prostate-specific antigen (PSA)-CreERT2 transgenic mouse strain expressing tamoxifen-inducible CreERT2 recombinase driven by a 6-kb human PSA promoter/enhancer was crossed with the B6.129-Cdh1tm2Kem/J mouse to generate bigenic PSA-CreERT2/Cdh1-/- mice. Deletion of E-cadherin was induced by transient administration of tamoxifen when mice reached sexual maturity (7 weeks of age). At 21 to 23 weeks of age, the prostate, bladder, and prostatic urethra were examined histologically, and bladder function was assessed using void spot assays and cystometry. Mice with Cdh1 deletion had increased prostatic inflammation, prostatic epithelial hyperplasia, and stromal changes at 21 to 23 weeks of age, as well as changes in bladder voiding function compared with age-matched controls. Thus, loss of E-cadherin in the murine prostate could result in prostatic defects that are characteristic of BPH and LUTS, suggesting that E-cadherin downregulation could be a driving force in human BPH development and progression.

Prostatic osteopontin expression is associated with symptomatic benign prostatic hyperplasia

BACKGROUND

Male lower urinary tract symptoms (LUTS) occur in more than half of men above 50 years of age. LUTS were traditionally attributed to benign prostatic hyperplasia (BPH) and therefore the clinical terminology often uses LUTS and BPH interchangeably. More recently, LUTS were also linked to fibrogenic and inflammatory processes. We tested whether osteopontin (OPN), a proinflammatory and profibrotic molecule, is increased in symptomatic BPH. We also tested whether prostate epithelial and stromal cells secrete OPN in response to proinflammatory stimuli and identified downstream targets of OPN in prostate stromal cells.

METHODS

Immunohistochemistry was performed on prostate sections obtained from the transition zone of patients who underwent surgery (Holmium laser enucleation of the prostate) to relieve LUTS (surgical BPH, S-BPH) or patients who underwent radical prostatectomy to remove low-grade prostate cancer (incidental BPH, I-BPH). Images of stained tissue sections were captured with a Nuance Multispectral Imaging System and histoscore, as a measure of OPN staining intensity, was determined with inForm software. OPN protein abundance was determined by Western blot analysis. The ability of prostate cells to secrete osteopontin in response to IL-1β and TGF-β1 was determined in stromal (BHPrS-1) and epithelial (NHPrE-1 and BHPrE-1) cells by enzyme-linked immunosorbent assay. Quantitative polymerase chain reaction was used to measure gene expression changes in these cells in response to OPN.

RESULTS

OPN immunostaining and protein levels were more abundant in S-BPH than I-BPH. Staining was distributed across all cell types with the highest levels in epithelial cells. Multiple OPN protein variants were identified in immortalized prostate stromal and epithelial cells. TGF-β1 stimulated OPN secretion by NHPrE-1 cells and both IL-1β and TGF-β1 stimulated OPN secretion by BHPrS-1 cells. Interestingly, recombinant OPN increased the mRNA expression of CXCL1, CXCL2, CXCL8, PTGS2, and IL6 in BHPrS-1, but not in epithelial cell lines.

CONCLUSIONS

OPN is more abundant in prostates of men with S-BPH compared to men with I-BPH. OPN secretion is stimulated by proinflammatory cytokines, and OPN acts directly on stromal cells to drive the synthesis of proinflammatory mRNAs. Pharmacological manipulation of prostatic OPN may have the potential to reduce LUTS by inhibiting both inflammatory and fibrotic pathways.

Long-lasting bladder overactivity and bladder afferent hyperexcitability in rats with chemically-induced prostatic inflammation

BACKGROUND

Benign prostatic hyperplasia (BPH) is one of the major causes of lower urinary tract symptoms (LUTS), including storage LUTS such as urinary frequency and urgency. Recently, a growing number of clinical studies indicate that prostatic inflammation could be an important pathophysiological mechanism inducing storage LUTS in patients with BPH. Here we aimed to investigate whether nonbacterial prostatic inflammation in a rat model induced by intraprostatic formalin injection can lead to long-lasting bladder overactivity and changes in bladder afferent neuron excitability.

METHODS

Male Sprague-Dawley rats were divided into four groups (n = 12 each): normal control group, 1-week prostatic inflammation group, 4-week inflammation group, and 8-week inflammation group. Prostatic inflammation was induced by formalin (10%; 50 µL per lobe) injection into bilateral ventral lobes of the prostate. Voiding behavior was evaluated in metabolic cages for each group. Ventral lobes of the prostate and the bladder were then removed for hematoxylin and eosin (HE) staining to evaluate inflammation levels. Continuous cystometrograms (CMG) were recorded to measure intercontraction intervals (ICI) and voided volume per micturition. Whole-cell patch clamp recordings were performed on dissociated bladder afferent neurons labeled by fluorogold injected into the bladder wall, to examine the electrophysiological properties.

RESULTS

Results of metabolic cage measurements showed that formalin-treated rats exhibited significantly (P < 0.05) increases in micturition episodes/12 hours and decrease in voided volume per micturition at every time point post injection. Continuous CMG illustrated the significant ( P < 0.05) higher number of nonvoiding contractions per void and shorter ICI in formalin-treated rats compared with control rats. HE staining showed significant prostatic inflammation, which declined gradually, in prostate tissues of formalin-induced rats. In patch clamp recordings, capsaicin-sensitive bladder afferent neurons from rats with prostatic inflammation had significantly ( P < 0.05) lower thresholds for spike activation and a "multiple" firing pattern compared with control rats at every time point post injection.

CONCLUSIONS

Formalin-induced prostatic inflammation can lead to long-lasting bladder overactivity in association with bladder afferent neuron hyperexcitability. This long-lasting model could be a useful tool for the study of inflammation-related aspects of male LUTS pathophysiology.

Urinary Metabolomic and Proteomic Analyses in a Mouse Model of Prostatic Inflammation

Lower urinary tract symptoms (LUTS) are common among aging men. Since prostatic inflammation is one of its etiologies, it is plausible that urinary metabolite and protein biomarkers could be identified and used to diagnose inflammation-induced LUTS. We characterized the urine metabolome and proteome in a mouse model of bacterial-induced prostatic inflammation. Mass Spectrometry (MS)-based multi-omics analysis was employed to discover urinary protein and metabolite-based biomarkers. The investigation of isobaric dimethylated leucine (DiLeu) labeling on metabolites allowed metabolomics and proteomics analysis on the same liquid chromatography (LC)-MS platform. In total, 143 amine-containing metabolites and 1058 urinary proteins were identified and quantified (data are available via ProteomeXchange with identifier PXD018023); among them, 14 metabolites and 168 proteins were significantly changed by prostatic inflammation. Five metabolic pathways and four inflammation-related biological processes were potentially disrupted. By comparing our findings with urinary biomarkers identified in a mouse model of genetic-induced prostate inflammation and with those previously found to be associated with LUTS in older men, we identified creatine, haptoglobin, immunoglobulin kappa constant and polymeric Ig receptor as conserved biomarkers for prostatic inflammation associated with LUTS. These data suggest that these putative biomarkers could be used to identify men in which prostate inflammation is present and contributing to LUTS.

Association between oral pathogens and prostate cancer: building the relationship

BACKGROUND

Chronic inflammation and infections are associated with increased risk of prostate cancer development. There is considerable evidence that proves the interrelationship between bacterial/viral infections and carcinogenesis. Periodontitis is a chronic inflammatory disease triggered by gram-negative anaerobic bacteria. In this narrative review, we investigate the relationship between periodontal disease and prostate cancer by reviewing previous studies of the association and possible mechanisms that may explain this link.

METHODS

A comprehensive search for articles published was performed using the key words, "periodontal disease", "prostate disease", "prostate cancer", "prostatic inflammation". Thorough reviews of each study were conducted and assessed for eligibility, and data was summarized.

RESULTS

The role of inflammatory responses in the prostate as drivers of malignancy appears to be predisposed by periodontal pathogens and/or periodontitis inflammatory mediators.

CONCLUSION

Periodontal diseases might be associated with prostate cancer. However, the mechanism(s) explaining this relationship remains unclear and requires further elucidation.

Effect of tadalafil on chronic pelvic pain and prostatic inflammation in a rat model of experimental autoimmune prostatitis

BACKGROUND

Experimental autoimmune prostatitis (EAP) shares important clinical features with clinical chronic prostatitis/chronic pelvic pain. We investigated the effect of tadalafil on pelvic pain and prostatic inflammation in a rat EAP model.

METHODS

EAP was induced in rats by intradermal injection of rat prostate antigen and complete Freund's adjuvant on days 0 and 28. Rats were treated with tadalafil (2 mg/kg, p.o.; EAP-tadalafil) or vehicle (EAP-vehicle) once daily from day 0, while sham-operated animals were treated with vehicle only (Sham). Tactile allodynia was measured on days 28, 35, and 42 by applying von Frey filaments to the lower abdomen as an index of pelvic pain. On day 42, the plasma immunoglobulin G (IgG) concentration and the testosterone/estradiol ratio were measured and histopathological analysis of the prostate was performed.

RESULTS

Tactile allodynia in the pelvic region was observed on days 28, 35, and 42 after EAP induction. The tactile allodynia observed on day 42 was significantly reduced by repeated treatment with tadalafil. Plasma IgG concentrations increased after EAP induction but the increase was not changed by tadalafil treatment. Prostate tissues were characterized by epithelial necrosis, infiltration of neutrophils and/or lymphocytes to acini and stroma, and fibrosis, in addition to a high stroma-to-epithelium ratio. Tadalafil treatment significantly suppressed the severity of the lesions.

CONCLUSIONS

EAP rats developed pelvic pain, prostatic inflammation and increased plasma IgG concentrations. Tadalafil inhibited the chronic pelvic pain and prostatic inflammation, suggesting that its anti-inflammatory action may contribute to its blocking of pain development in the EAP model.

Does asymptomatic prostatic inflammation alter the outcome of transurethral resection of prostate?

Introduction

There is contradictory evidence in literature with respect to the association of asymptomatic prostatic inflammation on biopsy with complications of Transurethral Resection of Prostate. The aim of the present study was to evaluate the association of prostatitis in biopsy specimens of patients undergoing transurethral resection of prostate with bladder neck contracture (the primary end point) and other complications.

Material and methods

Patients who had undergone transurethral resection at a single centre between 2005 and 2010, with a minimum of 3 months follow-up were included. The study population was divided into two cohorts: those with inflammation on prostatic biopsy (Group A) and those without (Group B). These two groups were compared with respect to demographic data and pre-operative and intraoperative confounding factors. Immediate complications were documented using the modified Clavien-Dindo system and compared. Long term complications like bladder neck contracture, meatal stenosis, urethral stricture, and recurrent adenoma were also compared.

Results

Both groups were comparable except for Group A patients having a higher median resected weight (20 vs. 14 gms, p = 0.009). There was no significant difference between the groups with respect to the rate of bladder neck contracture and other long-term and short term complications on univariate and multivariate analysis. Larger resected weight of gland was associated with lower rate of bladder neck contracture on multivariate analysis (p = 0.019, Odds ratio: 0.937).

Conclusions

Presence of histologically confirmed prostatic inflammation is not associated with bladder neck contracture or other complications following transurethral resection. Smaller resected prostatic weight was associated with higher incidence of bladder neck contracture.

CD-163 correlated with symptoms (pain or discomfort) of prostatic inflammation

The purpose of this study is to identify significant immune-system related for symptom of patients with prostatic inflammation in order to investigate the etiology of prostatic inflammation which may relate to potentially chronic prostatitis (CP). We investigated the expression of immune system-related biomarkers such as Interleukin (IL) -6 (humoral immunity), CD-3 (T-lymphocyte), and CD-163 (macrophage) in prostate biopsy (PBx) specimens from patients with prostatic inflammation (without cancer) which had been neither clinically diagnosed benign prostatic hyperplasia nor chronic prostatitis. We examined the correlation between these markers' expressions and the symptom scores using the National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI), International Prostate Symptom Score (IPSS)/quality of life (QOL) which are the index for lower urinary tract symptoms (LUTS). Our results showed CD-163 (macrophage) reflected pain or discomfort on NIH-CPSI scores (P=0.0389 and r=0.3307) in the patients with prostatic inflammation; however, the control patients had no significant correlation between symptom scores and those immune-related markers' expression. These results suggest that pain or discomfort related to macrophages in the relationship between immune-system and the symptom of prostatic inflammation. In conclusion, CD-163, related to immune-system (macrophage), correlated with symptoms (pain or discomfort) of prostatic inflammation and might represent a significant immune-system related biomarker for pain or LUTS score in potentially CP.