Comparative effectiveness of oral drug therapies for lower urinary tract symptoms due to benign prostatic hyperplasia: a systematic review and network meta-analysis

Comparative efficacy and safety of alpha-blockers as monotherapy for benign prostatic hyperplasia: a systematic review and network meta-analysis

Despite the availability of various drugs for benign prostatic hyperplasia (BPH), alpha(α)-blockers are the preferred first-line treatment. However, there remains a scarcity of direct comparisons among various α-blockers. Therefore, this network meta-analysis (NMA) of randomized controlled trials (RCTs) aimed to evaluate the efficacy and safety of α-blockers in the management of BPH. A comprehensive electronic search covered PubMed, Embase, Ovid MEDLINE, and Cochrane Library until August 2023. The primary endpoints comprised international prostate symptom score (IPSS), maximum flow rate (Qmax), quality of life (QoL), and post-void residual volume (PVR), while treatment-emergent adverse events (TEAEs) were considered as secondary endpoints. This NMA synthesized evidence from 22 studies covering 3371 patients with six kinds of α-blockers with 12 dose categories. IPSS has been considerably improved by tamsulosin 0.4 mg, naftopidil 50 mg and silodosin 8 mg as compared to the placebo. Based on the p-score, tamsulosin 0.4 mg had the highest probability of ranking for IPSS, PVR, and Qmax, whereas doxazosin 8 mg had the highest probability of improving QoL. A total of 297 adverse events were reported among all the α-blockers, silodosin has reported a notable number of TEAEs. Current evidence supports α-blockers are effective in IPSS reduction and are considered safer. Larger sample size with long-term studies are needed to refine estimates of IPSS, QoL, PVR, and Qmax outcomes in α-blocker users.

Isoform-independent promotion of contractility and proliferation, and suppression of survival by with no lysine/K kinases in prostate stromal cells

With no lysine/K kinases (WNKs) promote vasocontraction and vascular smooth muscle cell proliferation. In the prostate, smooth muscle contraction and growth may be critical for the development and medical treatment of voiding symptoms in benign prostatic hyperplasia. Here, we examined the effects of isoform-specific WNK silencing and of the WNK inhibitor WNK463 on growth-related functions and contraction in prostate stromal cells, and in human prostate tissues. Impacts of WNK silencing by transfection of cultured stromal cells with isoform-specific siRNAs were qualitatively and quantitatively similar for each WNK isoform. Effects of silencing were largest on cell death (3-5 fold increase in annexin V-positive/7-AAD-positive cells), on proliferation rate, Ki-67 mRNA expression and actin organization (reduced around two-thirds). Contraction in matrix contraction assays and viability were reduced to a lower degree (approximately half), but again to a similar extent for each WNK isoform. Effects of silencing were quantitatively and qualitatively reproduced by 10 μM WNK463, while 1 μM still induced cell death and breakdown in actin organization, without affecting proliferation or viability. Using 500 nM and 10 μM, WNK463 partly inhibited neurogenic and U46619-induced contractions of human prostate tissues (around half), while inhibition of α1-adrenergic contractions (around half) was limited to 10 μM. All four WNK isoforms suppress cell death and promote proliferation in prostate stromal cells. WNK-driven contraction of stromal cells appears possible, even though to a limited extent. Outcomes of isoform-specific WNK silencing can be fully reproduced by WNK463, including inhibition of smooth muscle contraction in human prostate tissues, but require high concentrations.

[Conservative and pharmacological treatment of benign prostatic hyperplasia : The German S2e-guideline 2023-part2]

BACKGROUND

Lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH, in German guidelines: benign prostatic syndrome [BPS]) is considered the most common disease of the lower urinary tract in men and can have a tremendous impact on the quality-of-life of affected patients. Conservative and pharmacological therapy of this disease are of great importance, both in improving LUTS and reducing progression-related complications.

OBJECTIVES

Presentation of the conservative and pharmacological treatment options according to the current German S2e guideline on BPS.

MATERIALS AND METHODS

Summary and overview of chapters 9 and 10 of the current German S2e guideline on BPS.

RESULTS

In addition to a controlled watchful waiting for BPS patients without an absolute indication for prostate surgery, a variety of phytopharmacological formulations and synthetic drugs according to the symptomatology and clinical progress are available. Phytotherapy should, due to inconsistent study data, only be considered for mild to moderate symptoms. Synthetic drugs include alpha-blockers, 5α-reductase inhibitors, phosphodiesterase inhibitors, antimuscarinics and, more recently, the β3-agonist mirabegron in the current guideline. In addition, various combination therapies are listed and evaluated according to their indications, effects and side effects.

CONCLUSIONS

The current German S2e guideline on the diagnosis and treatment of BPS provides an evidence-based foundation for finding the best possible and most effective medication.

A Review of Combined Phosphodiesterase-5-Inhibitors and α-Blockers versus Phosphodiesterase-5-Inhibitors Alone for Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia

Guidelines from the American Urological Association (AUA) and the European Association of Urology (EAU) present conflicting recommendations regarding combination therapy of phosphodiesterase 5 inhibitors (PDE5is) with α-blockers to treat benign prostatic hyperplasia (BPH) with lower urinary tract symptoms (LUTS). Use of PDE5is is widespread in the population of patients with LUTS/BPH. In this scoping review, we examine the evidence regarding the safety and efficacy of combined PDE5is and α-blockers compared to PDE5i medications alone. A search was conducted using PubMed, Cochrane, and Web of Science to identify manuscripts discussing the safety of PDE5i and α-blockers in combination or comparing this combination to PDE5is alone in the treatment of LUTS/BPH. Study designs, data, and conclusions were qualitatively analyzed. Combination therapy was found to be safe across all studies; importantly, no evidence documents increased risk of hypotension. Most studies reported added improvement in symptom and quality of life scores compared to PDE5i alone, with additional International Prostate Symptom Score (IPSS) change ranging from -1.30 to -8.50 and IPSS quality of life score change ranging from -0.15 to -1.50. Objective metrics such as postvoid residual volumes and maximum flow rate were inconsistently reported. Taken together, the current body of data suggests that combining PDE5i α-blocker therapy is safe and that there are opportunities for additional symptomatic improvement, though it should be utilized for select patients. Situations with particular utility could include patients with comorbid erectile dysfunction or without sufficient improvement on monotherapy.

Weak association between arterial hypertension and overactive bladder baseline symptoms and treatment responses

While animal studies have suggested an association between the presence of hypertension and the presence and/or severity of overactive bladder syndrome (OAB) symptoms, little clinical data is available. We have conducted a pre-specified secondary analysis of a non-interventional study involving 4450 OAB patients being treated with solifenacin to explore the existence of an association between OAB and hypertension using three parallel and overlapping definitions of hypertension to enhance robustness of analysis. Regardless of definition, patients with hypertension were older and had greater OAB symptom severity in univariate analyses. In multiple regression models including age as explanatory covariate, most relationships held up but effect sizes of concomitant hypertension on OAB severity were small (odds ratios <1.35 in all cases) and were deemed to be unlikely of clinical relevance. % Changes in symptom severity were somewhat smaller in univariate analysis, but effect sizes were small. We conclude that OAB and arterial hypertension are associated but effect sizes are too small to justify adaptation of clinical practice for OAB patients with concomitant hypertension.

Comparative Efficacy of Different Drugs for Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia: A Bayesian Network Meta-Analysis

Background: Lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia (BPH) are common in middle-aged and elderly men. The current drugs for treating this disease include α1-adrenoceptor antagonists (ABs), muscarinic receptor antagonists (MRAs), phosphodiesterase five inhibitors (PDE5-Is), and β3-adrenoceptor agonists (B3As). However, direct comparative studies analyzing different therapies are limited; therefore, we conducted a network meta-analysis (NMA) to evaluate the efficacy of different drug regimens for treating BPH/LUTS. Methods: The PubMed, EMbase, Web of Science, and Cochrane Library databases were searched to collect randomized controlled trials (RCTs) of different drug treatments for BPH/LUTS from January 2000 to April 2021. The NMA was performed using R 4.1 software. Results: Fifty-five RCTs were included among a total of 1639 trials. ① ABs + PDE5-Is, ABs + B3As, ABs + MRAs, ABs, and PDE5-IS were superior to the placebo in improving the total International Prostate Symptom Score (IPSS), IPSS-Voiding, and IPSS-storage. ② For increasing the maximum flow rate (Qmax), ABs + PDE5-Is, ABs + MRAs, and ABs were more effective than the placebo. ③ Regarding reducing post-void residual urine (PVR), none of the six treatment plans had significant effects. Conclusion: Combination therapy showed greater efficacy than monotherapy, and ABs + PDE5-Is was the most successful treatment for improving the overall IPSS score. ABs are a primary therapeutic measure to increase Qmax, and ABs + PDE5-I may be a more suitable choice for enhancing Qmax. The combination of MRA and AB+ MRA may lead to an increase in PVR. Systematic Review Registration: [website], identifier [registration number].

A Review of Aging and the Lower Urinary Tract: The Future of Urology

Lower urinary tract symptoms (LUTS) are common among elderly people, with significant effects on individuals, caregivers, and the wider health care system. As the elderly population with multiple comorbidities is increasing, the burden of LUTS will increase. This review describes the demographic trends in the aging society, changes in lower urinary tract function with aging, and deterioration of physical and cognitive function in aging, as well as what has been done regarding geriatric urology and what urologists should do to meet the health care needs of the aging population. Frailty and dementia are unmissable factors in the evaluation of elderly patients. Numerous reports have described associations between LUTS and frailty and between LUTS and dementia. Urologists must be aware of the multiplex physical, cognitive, and social characteristics of elderly people. Maintaining a geriatric viewpoint in the diagnosis, treatment, and management of elderly individuals with LUTS will fulfill the unmet needs of elderly people. It is also essential to discuss the treatment and management goals of LUTS with patients and caregivers. Active case identification, appropriate evaluations of LUTS and comorbidities, and a multidisciplinary approach with other health-care professionals are recommended for better treatment and management.

Inhibition of human prostate stromal cell growth and smooth muscle contraction by thalidomide: A novel remedy in LUTS?

BACKGROUND

Medical treatment in benign prostatic hyperplasia targets prostate size to prevent disease progression, complications, and surgery, and prostate smooth muscle tone for rapid relief of lower urinary tract symptoms. Combination therapies are still required to target both at once. However, current medications are insufficient, due to an unfavorable balance between side effects and efficacy. The limited efficacy of α₁ -blockers may be due to nonadrenergic mediators like endothelin-1 and thromboxane A₂ (TXA₂ ), which keep up prostate smooth muscle contraction even in the presence of α₁ -blockers. Consequently, future options with higher efficacy need to target α₁ -adrenergic and nonadrenergic contractions as well as stromal cell growth at once. Thalidomide has been approved as an oral medication for various diseases, including the treatment of prostate cancer. Therefore, we investigated the effect of thalidomide on cellular functions of prostate stromal cells and human prostate smooth muscle contraction.

METHODS

Cytoskeletal organization was visualized by phalloidin staining, cell growth was assessed by 5-ethynyl-2'-deoxyuridine assay, cell viability by cell counting kit-8, and apoptosis and cell death by flow cytometry in cultured prostate stromal cells (WPMY-1). Contractions of human prostate tissues from radical prostatectomy were studied in an organ bath, where they were induced by the α₁ -adrenoceptor agonists methoxamine, noradrenaline, phenylephrine, and the nonadrenergic agonists endothelin-1, TXA₂ analog U46619, or electric field stimulation (EFS).

RESULTS

Thalidomide significantly reduced the proliferation of WPMY-1 cells, which was time- and concentration-dependent (10-300 µM). In parallel, organization of actin filaments collapsed after treatment with thalidomide. Thalidomide (30-100 µM) inhibited noradrenaline-, phenylephrine-, and methoxamine-induced contractions, as well as nonadrenergic contractions induced by endothelin-1 and U46619, and neurogenic contractions induced by EFS. No reduction in viability and no increases in apoptosis or in cell death were observed in WPMY-1 cells.

CONCLUSIONS

Thalidomide impairs the growth of human prostate stromal cells, without showing a decrease in cell viability. In parallel, thalidomide inhibits adrenergic, neurogenic, and nonadrenergic contractions. This may be explained by a breakdown of the actin cytoskeleton. In vivo, urodynamic effects of thalidomide appear possible and may even exceed those of α₁ -blockers or combination therapies.

Pharmacological and interventional treatment of benign prostatic obstruction: An evidence‐based comparative review

Introduction

The recommended treatment for bothersome lower urinary tract symptoms (LUTS) secondary to benign prostatic obstruction (BPO) after the failure of behavioral therapy and fluid modification includes pharmacological, minimally invasive interventional, and surgical approaches. Each option has different risk and benefit profiles, and the urologist must be aware of the unique characteristics of each option in order to be able to accurately counsel the patients based on their individual values and preferences. We provide a comparative review of the commonest pharmacological and most widely performed interventional/surgical treatments for BPO, discussing the evidence for the treatment characteristics that are most useful for the practicing urologist.

Methods

A search of the PubMed database was performed for articles reporting on the following treatments for LUTS due to BPO: α‐blockers, 5α‐reductase inhibitors, phosphpdiesterase‐5 inhibitors, prostatic urethral lift (Urolift), convective radiofrequency water vapor thermal therapy (Rezum), Temporary implantable Nitinol Device (iTIND), prostate artery embolization (PAE), transurethral resection of the prostate (TURP), photoselective vaporization of the prostate (PVP), Aquablation, and anatomical endoscopic enucleation of the prostate (AEEP). We performed a narrative review focussing on the following outcomes: efficacy, safety, durability, duration of catheterization, length of stay, re‐treatment rate, efficacy in special situations (enlarged median lobe, prostate size, urinary retention, and anticoagulant use), and sexual adverse events.

Results

AEEP offers the greatest long‐term improvement in maximum flow rate, IPSS, and prostate volume reduction, with lowest re‐treatment rate, followed by PVP, TURP, and Aquablation. Urolift, Rezum, and PAE have similar efficacy for prostate volume up to 80cc, and all are more effective than the pharmacological treatment. Urolift offers the lowest rate of sexual dysfunction, followed by Rezum, and both can be performed as a day case under local anesthesia.

Conclusion

Several treatment options exist to treat voiding LUTS due to BPO. Newer minimally invasive treatments reduce the hospital stay and postoperative complications, whereas AEEP provides the greatest long‐term symptom improvement at the expense of higher morbidity and sexual dysfunction. Men should be counseled regarding all suitable treatment options as some may favor reduced efficacy in association with reduced side effects.

Purinergic smooth muscle contractions in the human prostate: estimation of relevance and characterization of different agonists

Non-adrenergic prostate smooth muscle contractions may account for the limited effectiveness of α₁-adrenoceptor antagonists, which are the first-line option for medical treatment of voiding symptoms suggestive of benign prostatic hyperplasia. In non-human prostates, purinergic agonists induce contractions reaching similar magnitudes as α₁-adrenergic contractions. However, evidence for the human prostate is highly limited, and pointed to much weaker purinergic contractions. Here, we examined contractions of different purinergic agonists in human prostate tissues. Tissues were obtained from radical prostatectomy. Contractions were studied in an organ bath, and expression of purinergic receptors was studied by RT-PCR. Electric field stimulation (EFS)–induced contractions amounted to 104% of KCl-induced contractions (95% CI: 84–124%). From all tested agonists, only ATP induced concentration-dependent contractions, reaching an average maximum of 18% (12–24%) of KCl. Maximum tensions following application of other agonists averaged to 7.1% of KCl for α,β-methylene-ATP (1.8–12.4%), 3.9% for β,γ-methylene-ATP (2.0–5.4%), 3.1% for 2-methylthio-ATP (− 0.1–6.3%), and 5.1% for ATPγS (1.0–9.2%). Responses were not affected by the P2X antagonist NF023 or the P2Y antagonist PPADS. mRNA expression of P2X1-4 correlated with expression of a marker for catecholaminergic nerves, although neither ATP, NF023, nor PPADS changed EFS-induced contractions. Correlation between expression of receptors and the smooth muscle marker calponin was not observed. Our findings point to a low relevance of purinergic contractions in the human prostate, compared to other contractile stimuli in the human prostate and compared to purinergic contractions in non-human prostates. Purinergic contractions in the human prostate are not sensitive to NF023 or PPADS.

Changes in the expression and function of the PDE5 pathway in the obstructed urinary bladder

Our study aims to explore changes in bladder contractility and the phosphodiesterase type 5 (PDE5) signalling pathway in response to partial bladder outlet obstruction (PBOO). A surgically induced male rat PBOO model and human obstructed bladder tissues were used. Histological changes were examined by H&E and Masson's trichrome staining. Bladder strip contractility was measured via organ bath. The expressions of nitric oxide synthase (NOS) isoforms, PDE5, muscarinic cholinergic receptor (CHRM) isoforms and PDE4 isoforms in bladder were detected by RT‐PCR and Western blotting. The immunolocalization of the PDE5 protein and its functional activity were also determined. PBOO bladder tissue exhibited significant SM hypertrophy and elevated responsiveness to KCl depolarization and the muscarinic receptor agonist carbachol. NOS isoforms, PDE5, CHRM2, CHRM3 and PDE4A were up‐regulated in obstructed bladder tissue, whereas no change in PDE4B and PDE4D isoform expression was observed. With regard to PDE5, it was expressed in the SM bundles of bladder. Interestingly, obstructed bladder exhibited less relaxation responsiveness to sodium nitroprusside (SNP), but an exaggerated PDE5 inhibition effect. The up‐regulation of PDE5 could contribute to the lack of effect on Q_max for benign prostatic hyperplasia/lower urinary tract symptom (BPH/LUTS) patients treated with PDE5 inhibitors. Moreover, PDE5 (with presence of NO) and PDE4 may serve as new therapeutic targets for bladder diseases such as BPH‐induced LUTS and overactive bladder (OAB).

Inhibition of neurogenic and thromboxane A2 -induced human prostate smooth muscle contraction by the integrin α2β1 inhibitor BTT-3033 and the integrin-linked kinase inhibitor Cpd22

INTRODUCTION

Prostate smooth muscle contraction is critical for etiology and treatment of lower urinary tract symptoms in benign prostatic hyperplasia (BPH). Integrins connect the cytoskeleton to membranes and cells to extracellular matrix, what is essential for force generation in smooth muscle contraction. Integrins are composed of different subunits and may cooperate with integrin-linked kinase (ILK). Here, we examined effects of inhibitors for different integrin heterodimers and ILK on contraction of human prostate tissues.

METHODS

Prostate tissues were obtained from radical prostatectomy. Integrins and ILK were detected by Western blot, real-time polymerase chain reaction (RT-PCR), and double fluorescence staining. Smooth muscle contractions of prostate strips were studied in an organ bath. Contractions were compared after application of solvent (controls), the ILK inhibitor Cpd22 (N-methyl-3-(1-(4-(piperazin-1-yl)phenyl)-5-(4'-(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-1H-pyrazol-3-yl)propanamide), the integrin α2β1 inhibitor BTT-3033 (1-(4-fluorophenyl)-N-methyl-N-[4[[(phenylamino)carbonyl]amino]phenyl]-1H-pyrazole-4-sulfonamide), or the integrin α4β1/α9β1 inhibitor BOP (N-(benzenesulfonyl)- l-prolyl- l-O-(1-pyrrolidinylcarbonyl)tyrosine sodium salt).

RESULTS

Western blot analyses of prostate tissues using antibodies raised against integrins α2b, α4, α9, β1, and ILK revealed bands matching the expected sizes of corresponding antigens. Expression of integrins and ILK was confirmed by RT-PCR. Individual variations of expression levels occurred independently from divergent degree of BPH, reflected by different contents of prostate-specific antigen. Double fluorescence staining of prostate sections using antibodies raised against integrins α2 and β1, or against ILK resulted in immunoreactivity colocalizing with calponin, suggesting localization in prostate smooth muscle cells. Electric field stimulation (EFS) induced frequency-dependent contractions, which were inhibited by Cpd22 (3 µM) and BTT-3033 (1 µM) (inhibition around 37% by Cpd22 and 46% by BTT-3033 at 32 Hz). The thromboxane A₂ analog U46619-induced concentration-dependent contractions, which were inhibited by Cpd22 and BTT-3033 (around 67% by Cpd22 and 39% by BTT-3033 at 30 µM U46619). Endothelin-1 induced concentration-dependent contractions, which were not affected by Cpd22 or BTT-3033. Noradrenaline and the α₁ -adrenergic agonists methoxamine and phenylephrine-induced concentration-dependent contractions, which were not or very slightly inhibited by Cpd22 and BTT-3033. BOP did not change EFS- or agonist-induced contraction.

CONCLUSIONS

Integrin α2β1 and ILK inhibitors inhibit neurogenic and thromboxane A₂ -induced prostate smooth muscle contraction in human BPH. A role for these targets for prostate smooth muscle contraction may appear possible.

Effects of Tamsulosin Combined With Solifenacin on Lower Urinary Tract Symptoms: Evidence From a Systematic Review, Meta-Analysis, and Trial Sequential Analysis of Randomized Controlled Trials

This study is aimed to systematically evaluate the efficacy of tamsulosin combined with solifenacin and provide clinical evidence for treatment of benign prostatic hyperplasia (BPH) with lower urinary tract symptoms (LUTS). PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and Wanfang data information service platform were searched to select randomized controlled trials (RCTs) of tamsulosin combined with solifenacin in the treatment of BPH with LUTS. After extraction of the data, the statistical information was calculated by means of STATA 12.0. The publication bias was calculated using Egger's test and Begg's funnel plot. A total of 17 articles contained 1,870 patients treated with tamsulosin in combination with solifenacin and 1,897 patients treated with tamsulosin only were included in this study. Results show that tamsulosin combined with solifenacin therapy was more effective in reducing the Total International Prostate Symptom Score (TIPSS), Storage International Prostate Symptom Score (SIPSS), Quality of life (QOL), and Overactive bladder symptom score (OABSS) in comparison with tamsulosin monotherapy treatment. However, it was found that the combination therapy may increase levels of prostate-specific antigen (PSA) and the maximal urinary flow rate (QMAX). Differences between the combination therapy and tamsulosin monotherapy were not statistically significant for urgency episodes per 24 h, micturitions per 24 h, Voiding International Prostate Symptom Score (VIPSS), and postvoid residual volume (PVR). Tamsulosin combined with solifenacin therapy is more effective than tamsulosin monotherapy for the treatment of BPH concurrent with LUTS and won't increase the risk of dysuria.

Add-on effects of tadalafil in tamsulosin-treated patients with small benign prostatic enlargement: A randomized, placebo-controlled, double-blind, crossover study

AIM

To assess the add-on effects of tadalafil in patients with a relatively small benign prostatic enlargement (BPE) treated with tamsulosin.

METHODS

From September 2014 to July 2018, we prospectively studied patients (aged 50 years or more) attending our hospital who had received tamsulosin for small BPE (20-40 mL) for 4 weeks at least and still had residual lower urinary tract symptoms (LUTS) with total International Prostate Symptom Scores (IPSS) of at least 8 and IPSS-quality of life scores at least 3. We randomized eligible patients into two groups: one of which received tadalafil 5 mg once daily for 6 weeks, followed by placebo for 6 weeks, and the other of which received placebo followed by tadalafil in the same manner. The patients were reviewed at our outpatient clinic after 2, 6, 8, and 12 weeks.

RESULTS

There were 13 patients in the tadalafil-placebo and 13 in the placebo-tadalafil group. Their median ages (range) were 70 (65-85) and 73 (50-80) years, prostatic volumes (median) 30.0 (22.0-39.7) and 32.0 (20.1-39.5) mL, and total IPSS (median) 17 (10-27) and 16 (10-24), respectively. The primary endpoints, namely mean changes of total IPSS from baseline, were 1.85 on placebo and -3.42 on tadalafil; this difference is statistically significant (difference: -1.57; 95% confidence interval: -3.00, -0.69; P = .032). We encountered no adverse effects.

CONCLUSIONS

Add-on of tadalafil for symptomatic patients with small BPE treated with tamsulosin appears to be effective and safe.

A NAV2729-sensitive mechanism promotes adrenergic smooth muscle contraction and growth of stromal cells in the human prostate

Voiding symptoms in benign prostatic hyperplasia (BPH) are driven by prostate smooth muscle contraction and prostate growth. Smooth muscle contraction in the prostate and other organs critically depends on activation of the small monomeric GTPase RhoA and probably Rac1. A role of another GTPase, ADP-ribosylation factor 6 (ARF6), for smooth muscle contraction has been recently suggested by indirect evidence but remains to be proven for any organ. Here, we report effects of NAV2729, an inhibitor with assumed specificity for ARF6, in human prostate tissues and cultured prostate stromal cells (WPMY-1). NAV2729 (5 μm) inhibited neurogenic and α₁-adrenergic contractions of human prostate tissues. Contractions induced by endothelin-1, by the thromboxane A₂ agonist U46619, or by high molar KCl were not inhibited. Correlation analyses suggested up-regulation of prostatic ARF6 expression with increasing degree of BPH, as ARF6 expression increased with the content of prostate-specific antigen (PSA) of prostate tissues. NAV2729 inhibited ARF6 activity but not other GTPases (ARF1, RhoA, Rac1) in prostate tissues and in WPMY-1 cells. Proliferation of WPMY-1 cells was inhibited concentration-dependently by NAV2726, as reflected by decreased viability, 5-ethynyl-2'-deoxyuridine (EdU) assay, colony formation assay, and expression of Ki-67. Silencing of ARF6 expression mimicked effects of NAV2729 on viability and in the EdU assay. Effects of NAV2729 on viability and proliferation were attenuated in cells with silenced ARF6 expression. Our findings suggest that a NAV2729-sensitive mechanism promotes adrenergic contraction and stromal cell growth in the human prostate, which is probably ARF6-mediated. Similar actions in other organs and urodynamic effects of NAV2729 appear possible.

Efficacy and tolerability of Roystonea regia lipid extract (D-004) and terazosin in men with symptomatic benign prostatic hyperplasia: a 6-month study

Background

Benign prostatic hyperplasia (BPH), a common urological disease in aging men, frequently produces lower urinary tract symptoms (LUTS). Clinical studies have shown that terazosin relaxes the smooth muscle of the prostate and bladder, facilitates bladder emptying, improves LUTS, increases maximum urinary flow, and reduces the residual volume of urine. D-004, a lipid extract of the fruit of the Cuban royal palm (Roystonea regia), presents a similar efficacy to Saw palmetto. Clinical studies have demonstrated its efficacy and safety in short- and medium-term trials in patients with BPH. The objective of this study was to compare the efficacy and tolerability of D-004 with terazosin for 6 months on LUTS in patients with BPH.

Methods

The present phase III study had an open, randomized, comparative design, with two parallel groups who received D-004 (320 mg/day) or terazosin (5 mg/day) for 6 months. The study included men at least 50 years of age, with evidence of the LUTS of moderate intensity according to the International Symptoms of the Prostate (IPSS). The effects on the IPSS Scale was the primary efficacy variable. The effects on the size of the prostate and the residual volume were secondary variables. The subjective self-perception of symptom relief at trial completion was a collateral outcome. Analysis was done by intention-to-treat.

Results

The study included 100 men with a diagnosis of BPH, confirmed by digital rectal examination and ultrasonography, and moderate LUTS (IPSS score >7, <19). Baseline characteristics were similar in both groups. Nine patients did not continue the study: one from group D-004 (due to protocol violation) and eight from the terazosin group (six due to adverse events and two due to protocol violation; p < 0.01). D-004 and terazosin significantly reduced the IPSS scores at the end of the 6 months of therapy by 74.2% and 66.1%, respectively, with respect to baseline values. Comparisons between groups performed showed that, at the end of the treatment, D-004 was more effective (p < 0.05) than terazosin in reducing the IPSS score. Although the average size of the prostate was reduced in both groups, this reduction reached statistical significance only for D-004. On the other hand, postvoid residual volume was significantly and similarly reduced in both groups. Both treatments were safe, while D-004 was better tolerated than terazosin.

Conclusions

D-004 administered at a dose of 320 mg/day for 6 months showed comparable efficacy with terazosin (5 mg/day) in reducing the LUTS (IPSS score), producing a significant decrease in prostate volume and postvoid residual volume. Both treatments were safe, with better tolerability for D-004 as compared with terazosin.

New strategies for inhibition of non-adrenergic prostate smooth muscle contraction by pharmacologic intervention

BACKGROUND

Inhibition of prostate smooth muscle contraction by α₁ -adrenoceptor antagonists (α₁ -blockers) is a first-line medical treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia. Increased smooth muscle tone in the hyperplastic prostate may drive urethral obstruction, resulting in bladder outlet obstruction and voiding symptoms. However, efficacy of α₁ -blockers is limited, as non-adrenergic mediators including endothelin-1 and thromboxane A₂ (TXA₂ ) increase prostate smooth muscle tension in parallel to α₁ -adrenoceptors. This may maintain urethral obstruction despite therapy with α₁ -blockers. Consequently, future treatment options with higher efficacy need to target α₁ -adrenergic and non-adrenergic contractions simultaneouly. Recently, several compounds were reported to inhibit adrenergic or neurogenic prostate contractions, however, their effects on non-adrenergic contraction are unknown. Here, we examined effects of inhibitors for Rac-GTPase, Src family kinases (SFKs), and p21-activated kinases (PAKs) on non-adrenergic prostate contractions.

METHODS

Prostate tissues were obtained from radical prostatectomy. Contractions were studied in an organ bath. Viability of cultured stromal cells was assessed by CCK-8 assay.

RESULTS

Inhibition of α₁ -adrenergic contractions by Rac inhibitors EHT1864 (100 μM) and NSC23766 (100 μM), and SFK inhibitors AZM475721 (10 μM) and PP2 (10 μM) was confirmed by inhibition of methoxamine-induced contractions. No effects of the PAK inhibitors FRAX486 (30 μM) and IPA3 (300 μM) on α₁ -adrenergic contraction were confirmed by absent effects on methoxamine-inuced contractions. EHT1864 caused inhibition of endothelin-1- and U46619-induced contractions. EHT1864 reduced the viability of stromal cells concentration- and time-dependently. EHT1864 attenuated KCl-induced contractions of prostate strips only slightly, so that toxic effects may not account alone for inhibition of agonist-induced contractions. NSC23766 inhibited U46619-induced contractions, but not endothelin-1-induced contractions. AZM475271 had no effects on endothelin-1- or U46619-induced contractions, while PP2 inhibited U46619- but not endothelin-1-induced contractions. FRAX486 caused inhibition of U46619-induced contractions. IPA3 inhibited U46619-, but not endothelin-1-induced contractions.

CONCLUSIONS

Of all six inhibitors, EHT1864 seems to be most promising from a translational point of view, as it inhibited TXA₂ - and endothelin-1-induced besides α₁ -adrenergic prostate contractions. This reflects divergent pharmacologic profiles of EHT1864 and NSC23766, although both are Rac-GTPase inhibitors. In vivo, urodynamic effects of EHT1864 and possibly of FRAX486 may exceed those of α₁ -blockers.

Sildenafil, a phosphodiesterase type 5 inhibitor, augments sphincter bursting and bladder afferent activity to enhance storage function and voiding efficiency in mice

Objectives

To investigate the influence of low‐dose sildenafil, a phosphodiesterase type 5 inhibitor (PDE5‐I), on the function of the mouse lower urinary tract (LUT).

Materials and Methods

Adult male mice were decerebrated and arterially perfused with a carbogenated Ringer's solution to establish the decerebrate arterially perfused mouse (DAPM). To allow distinction between central neural and peripheral actions of sildenafil, experiments were conducted in both the DAPM and in a ‘pithed’ DAPM, which has no functional brainstem or spinal cord. The action of systemic and intrathecal sildenafil on micturition was assessed in urethane‐anaesthetised mice.

Results

In the DAPM, systemic perfusion of sildenafil (30 pm) decreased the voiding threshold pressure [to a mean (sem) 84.7 (3.8)% of control] and increased bladder compliance [to a mean (sem) 140.2 (8.3)% of control, an effect replicated in the pithed DAPM]. Sildenafil was without effect on most voiding variables but significantly increased the number of bursts of the external urethral sphincter (EUS) per void in DAPM [to a mean (sem) 130.1 (6.9)% of control at 30 pm] and in urethane‐anaesthetised mice [to a mean (sem) 117.5 (5.8)% of control at 14 ng/kg]. Sildenafil (10 and 30 pm) increased pelvic afferent activity during both bladder filling and the isovolumetric phase [to a mean (sem) 205.4 (30.2)% of control at 30 pm]. Intrathecal application of sildenafil (5 μL of either 150 pm or 1.5 nm) did not alter cystometry and EUS‐electromyography variables in urethane‐anaesthetised mice.

Conclusions

Low‐dose sildenafil increases bladder compliance, increases pelvic nerve afferent activity, and augments the bursting activity of the EUS. We propose that the novel actions on afferent traffic and sphincter control may contribute to its beneficial actions to restore storage and voiding efficiency in LUT dysfunction.

Self-assessed goal achievement (SAGA) after Holmium laser enucleation of the prostate (HoLEP): Association with patients' postoperative satisfaction

This study aimed to determine serial changes in self-assessed goal achievement (SAGA) and treatment satisfaction after HoLEP, to identify correlations between the two, and to compare them with results assessed by traditional outcome measures. For a total of 170 patients, outcomes were evaluated serially at postoperative 1-, 3-, 6-, and 12-months using IPSS, OABSS, SAGA questionnaires and uroflowmetry. The SAGA questionnaire consisted of five questions including one open-ended question (self-assessed goals and degree of SAGA) and another question regarding treatment satisfaction. The number of self-assessed treatment goals was two or more in 74.1% of the patients. Most common treatment goal was relief from straining/hesitancy, followed by increased daytime frequency, nocturia and feeling of incomplete emptying. Degree of achievement for the first or second goal and treatment satisfaction tended to increase with time throughout the follow-up period. Patients with the greatest treatment satisfaction scores showed greater improvement by traditional outcome parameters including quality of life (QOL) index, total OABSS, maximum flow rate (Qmax), post-void residual urine volume (PVR) and bladder voiding efficiency (BVE) compared to those without treatment satisfaction. After adjusting for other influential variables, the improvements in subjective outcome parameters including total IPSS, QOL index and total OABSS were significantly associated with treatment satisfaction, but improvements in objective outcome parameters including Qmax, PVR and BVE were not. In addition, the degree of SAGA for the first goal or second goal was more predictive in determining treatment satisfaction than the traditional outcome measures. In conclusion, treatment goals of patients with lower urinary tract symptoms (LUTS)/BPH vary from individual to individual. The degree of SAGA and treatment satisfaction for HoLEP tends to increase with time throughout the follow-up period. Compared to the traditional outcome measures, the degree of goal achievement can be more predictive when assessing patient-centered outcomes such as treatment satisfaction.

PDE5 inhibitors - pharmacology and clinical applications 20 years after sildenafil discovery

The discovery of the nitric oxide/cGMP pathway was the basis for our understanding of many normal physiological functions and the pathophysiology of several diseases. Since the discovery and introduction of sildenafil, inhibitors of PDE5 have been the first-line therapy for erectile dysfunction (ED). The success of sildenafil in the treatment of ED stimulated research in the field of PDE5 inhibition and led to many new applications, such as treatment of lower urinary symptoms, and pulmonary arterial hypertension, which are now approved indications. However, PDE5 inhibitors have also been used in several other disorders not discussed in this review, and the fields of clinical use are increasing. In the present review, the pharmacological basis of the NO/cGMP pathway and the rationale and clinical use of PDE5 inhibitors in different diseases are discussed.

Novel imaging of the prostate reveals spontaneous gland contraction and excretory duct quiescence together with different drug effects

Prostate carcinoma and benign prostate hyperplasia (BPH) with associated lower urinary tract symptoms (LUTS) are among the most prevalent and clinically relevant diseases in men. BPH is characterized by an enlargement of prostate tissue associated with increased tone of smooth muscle cells (SMCs) which surround the single glands composing the prostate. Secretions of the glands leave the prostate through local excretory ducts during the emission phase of ejaculation. Pharmacological treatment of BPH suggests different local drug targets based on reduction of prostate smooth muscle tone as the main effect and disturbed ejaculation as a common side effect. This highlights the need for detailed investigation of single prostate glands and ducts. We combined structural and functional imaging techniques-notably, clear lipid-exchanged, acrylamide-hybridized rigid imaging/immunostaining/ in situ hybridization-compatible tissue-hydrogel (CLARITY) and time-lapse imaging-and defined glands and ducts as distinct SMC compartments in human and rat prostate tissue. The single glands of the prostate (comprising the secretory part) are characterized by spontaneous contractions mediated by the surrounding SMCs, whereas the ducts (excretory part) are quiescent. In both SMC compartments, phosphodiesterase (PDE)-5 is expressed. PDE5 inhibitors have recently emerged as alternative treatment options for BPH. We directly visualized that the PDE5 inhibitors sildenafil and tadalafil act by reducing spontaneous contractility of the glands, thereby reducing the muscle tone of the organ. In contrast, the ductal (excretory) system and thus the prostate's contribution to ejaculation is unaffected by PDE5 inhibitors. Our differentiated imaging approach reveals new details about prostate function and local drug actions and thus may support clinical management of BPH.-Kügler, R., Mietens, A., Seidensticker, M., Tasch, S., Wagenlehner, F. M., Kaschtanow, A., Tjahjono, Y., Tomczyk, C. U., Beyer, D., Risbridger, G. P., Exintaris, B., Ellem, S. J., Middendorff, R. Novel imaging of the prostate reveals spontaneous gland contraction and excretory duct quiescence together with different drug effects.

Safety and efficacy of tamsulosin, alfuzosin or silodosin as monotherapy for LUTS in BPH - a double-blind randomized trial

INTRODUCTION

Currently alpha1-adrenoceptor blockers (AB) are widely used as first-line therapy to improve lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). We compared the efficacy and safety profile of tamsulosin, alfuzosin and silodosin in LUTS due to BPH.

MATERIAL AND METHODS

Consecutive consenting male patients (N = 269) undergoing medical management of BPH with AB from February 2012 to October 2015 were enrolled. Patients were randomized to a 0.4 mg tamsulosin (group T), 10 mg alfuzosin (group A) or a 8 mg silodosin (group S) by double-blind randomization. All patients were assessed for improvements and post-void residual urine (PVR) and for adverse drug events (ADE).

RESULTS

IPSS showed significant improvement in Group S at the first week (11.7 ±4.18, p = 0.027) and at 3 months (7.97 ±3.84, p = 0.020). QOL showed significant improvement at 1 (2.2 ±0.76, p = 0.020), 4 (1.47 ±0.63, p <0.001) and 12 (1.2 ±0.66, p <0.001) weeks in Group S. The mean Qmax improvement was the maximum (13.76 ±2.44, p = 0.028) in Group S at 1 week. Reduction in PVR was the maximum in Group S, but it was not statistically significant. Adverse drug events (ADE) were observed in 20.07% (54/269) patients and distribution was similar in the three groups with decreasing incidence with progression of time.

CONCLUSIONS

Silodosin is the most efficacious AB with rapid onset of action. Silodosin also improves the quality of life in patients with LUTS due to BPH and objectively improves maximum flow rate. However, silodosin has more adverse events when compared to tamsulosin and alfuzosin.

Non-Adrenergic, Tamsulosin-Insensitive Smooth Muscle Contraction is Sufficient to Replace α1 -Adrenergic Tension in the Human Prostate

BACKGROUND

Lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia may be caused by prostate smooth muscle contraction. Although α₁ -blockers may improve symptoms by prostate smooth muscle relaxation, their efficacy is limited. This may be explained by non-adrenergic mediators causing contraction in parallel to α₁ -adrenoceptors. However, little is known about the relevance and cooperative actions of non-adrenergic mediators in the prostate.

METHODS

Prostate tissues were obtained from radical prostatectomy (n = 127 patients). Contractile responses were studied in an organ bath.

RESULTS

Endothelin-1 and noradrenaline induced contractions of similar magnitude (116 ± 23 and 117 ± 18% of KCl-induced contractions). Endothelin-2- and -3-induced maximum contractions of 63 ± 8.6 and 71 ± 19% of KCl, while contractions by the thromboxane analog U46619 amounted up to 63 ± 9.4%. Dopamine-induced contractions averaged to 22 ± 4.5% of KCl, while maximum contractions by serotonin, histamine, and carbachol stayed below 10% of KCl-induced. While noradrenaline-induced contractions were inhibited by tamsulosin (300 nM), endothelin-1-, -2-, or -3-induced contraction were not. No additive effects were observed if endothelins and noradrenaline were applied consecutively to the same samples. If endothelin-1 was applied after U46619, resulting tension (172 ± 43% of KCl) significantly exceeded noradrenaline-induced contraction. Tensions following combined application of endothelin-2 or -3 with U46619 stayed below noradrenaline-induced contractions. Tension following combined application of all three endothelins with U46619 resembled maximum noradrenaline-induced tone.

CONCLUSIONS

Contractions following concomitant confrontation of human prostate tissue with noradrenaline and endothelin-1 are not additive. Endothelin-1 is sufficient to induce a smooth muscle tone resembling that of noradrenaline. This may replace lacking α₁ -adrenergic tone under therapy with α₁ -blockers, explaining the limited efficacy of α₁ -blockers in LUTS treatment. Contractions by thromboxane and endothelin-1 may be additive, and may exceed α₁ -adrenergic tone. Prostate 77:697-707, 2017. © 2017 Wiley Periodicals, Inc.

Clinical and preclinical treatment of urologic diseases with phosphodiesterase isoenzymes 5 inhibitors: an update

Phosphodiesterase isoenzymes 5 inhibitors (PDE5-Is) are the first-line therapy for erectile dysfunction (ED). The constant discoveries of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) cell-signaling pathway for smooth muscle (SM) control in other urogenital tracts (UGTs) make PDE5-Is promising pharmacologic agents against other benign urological diseases. This article reviews the literature and contains some previously unpublished data about characterizations and activities of PDE5 and its inhibitors in treating urological disorders. Scientific discoveries have improved our understanding of cell-signaling pathway in NO/cGMP-mediated SM relaxation in UGTs. Moreover, the clinical applications of PDE5-Is have been widely recognized. On-demand PDE5-Is are efficacious for most cases of ED, while daily-dosing and combination with testosterone are recommended for refractory cases. Soluble guanylate cyclase (sGC) stimulators also have promising role in the management of severe ED conditions. PDE5-Is are also the first rehabilitation strategy for postoperation or postradiotherapy ED for prostate cancer patients. PDE5-Is, especially combined with α-adrenoceptor antagonists, are very effective for benign prostatic hyperplasia (BPH) except on maximum urinary flow rate (Q max ) with tadalafil recently proved for BPH with/without ED. Furthermore, PDE5-Is are currently under various phases of clinical or preclinical researches with promising potential for other urinary and genital illnesses, such as priapism, premature ejaculation, urinary tract calculi, overactive bladder, Peyronie's disease, and female sexual dysfunction. Inhibition of PDE5 is expected to be an effective strategy in treating benign urological diseases. However, further clinical studies and basic researches investigating mechanisms of PDE5-Is in disorders of UGTs are required.

Placebo Medication and Sham Surgery Responses in Benign Prostatic Hyperplasia Treatments: Implications for Clinical Trials

Placebo medications and sham surgeries have long been thought to be inert treatments. These groups served as a threshold to which an active treatment should be compared in a randomized trial to determine the true efficacy of the active treatment. However, surprising changes in subjective symptom scores and objective measures of voiding have been demonstrated in numerous placebo medication or sham surgery arms of trials. The exact mechanisms by which these inactive treatments augment patient outcomes are not clearly defined and multiple theories have been proposed to explain the often pronounced response. It appears that urologic outcomes are particularly prone to these effects and the astute physician should keep these responses in mind when interpreting any trial on a new therapy.

Latest Evidence on the Use of Phosphodiesterase Type 5 Inhibitors for the Treatment of Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia

CONTEXT

Several preclinical reports, randomized controlled trials, systematic reviews, and posthoc analyses corroborate the role of phosphodiesterase type 5 inhibitors (PDE5-Is) in the treatment of men with lower urinary tract symptoms (LUTS) associated with benign prostatic enlargement (BPE).

OBJECTIVE

Update of the latest evidence on the mechanisms of action, evaluate the current meta-analyses, and emphasize the results of pooled data analyses of PDE5-Is in LUTS/BPE.

EVIDENCE ACQUISITION

Literature analysis of basic researches on PDE5-Is, systematic literature search in PubMed and Scopus until May 2015 on reviews of trials on PDE5-Is, and collection of pooled data available on tadalafil 5mg.

EVIDENCE SYNTHESIS

Latest evidences on the pathophysiology of LUTS/BPE has provided the rationale for use of PDE5-Is: (1) improvement of LUT oxygenation, (2) smooth muscle relaxation, (3) negative regulation of proliferation and transdifferentiation of LUT stroma, (4) reduction of bladder afferent nerve activity, and (5) down-regulation of prostate inflammation are the proven mechanisms of action of PDE5-Is. Data from eight systematic reviews demonstrated that PDE5-Is allow to improve LUTS (International Prostate Symptom Score mean difference vs placebo: 2.35-4.21) and erectile function (International Index of Erectile Function mean difference vs placebo: 2.25-5.66), with negligible change in flow rate (Qmax mean difference vs placebo: 0.01-1.43). Pooled data analyses revealed that tadalafil 5mg once daily allows the clinically-meaningful improvement of LUTS and nocturnal voiding frequency independent of both erectile dysfunction severity and improvement.

CONCLUSIONS

PDE5-Is are safe and effective in improving both LUTS and erectile function in appropriately selected men with LUTS/BPE. Data on the reduction of disease progression, long-term outcomes, and cost-effectiveness analyses are still lacking.

PATIENT SUMMARY

We reviewed recent literature on phosphodiesterase type 5 inhibitors in men with lower urinary tract symptoms associated with prostatic enlargement. We found evidence to confirm that phosphodiesterase type 5 inhibitors are a valid treatment option for men affected by bothersome urinary symptoms with or without erectile dysfunction.

Upregulation of Phosphodiesterase type 5 in the Hyperplastic Prostate

Both erectile dysfunction (ED) and lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH) are common in the aging male. Numerous clinical trials have demonstrated the efficacy and safety of phosphodiesterase type 5 inhibitors (PDE5-Is) for treating LUTS/BPH with/without ED. However, the influence of BPH on prostatic PDE5 expression has never been studied. A testosterone-induced rat model of BPH was developed and human hyperplastic prostate specimens were harvested during cystoprostatectomy. PDE5, nNOS, eNOS and α₁-adrenoreceptor subtypes (α_1aARs, α_1bARs and α_1dARs) were determined with real-time RT-PCR for rat tissues whilst PDE5 and α₁-adrenoreceptor subtypes were determined in human samples. PDE5 was further analyzed with Western-blot and histological examination. Serum testosterone was measured with ELISA. The rat BPH model was validated as having a significantly enlarged prostate. PDE5 localized mainly in fibromuscular stroma in prostate. Our data showed a significant and previously undocumented upregulation of PDE5 in both rat and human BPH, along with increased expression of nNOS and α_1dARs for rat tissues and α_1aARs for human BPH. The upregulation of PDE5 in the hyperplastic prostate could explain the mechanism and contribute to the high effectiveness of PDE5-Is for treating LUTS/BPH. Fibromuscular stroma could be the main target for PDE5-Is within prostate.

Combination therapy with tamsulosin and solifenacin for male lower urinary tract symptoms with predominant filling symptoms: a new approach to an old problem

Benign prostatic enlargement is the main cause of male lower urinary tract symptoms (LUTS). The distinction and quantification of voiding, storage and postmicturition symptoms help clinicians decide on a modern pharmacological therapeutic approach for male LUTS. Muscarinic receptors antagonists are now considered safe therapy in males and a fixed-dose combination of oral controlled absorbed system solifenacin and tamsulosin is advantageous compared to tamsulosin monotherapy in males with predominant storage symptoms when validated instruments such as International Prostatic Score Symptoms (IPSS) or Total Urgency Frequency Score (TUFS) are used. This combination therapy is well tolerated and maintains symptomatic improvement in the long term. Different options of managing male LUTS with predominant storage symptoms include a combination of tamsulosin and solifenacin, antimuscarinics alone - some with flexible dosing, and the beta-3 agonist mirabegron. Tailored pharmacological therapy for the particular patient is not a reality yet, but judicious use of the different alternatives could bring varied new therapeutic solutions for male LUTS including benign prostatic enlargement and benign prostatic obstruction.

The role of phosphodiesterase-5 inhibitors in prostatic inflammation: a review

Clinical and basic experimental evidence indicates that chronic inflammation is the greatest factor in benign prostatic hyperplasia (BPH) progression, which is the most common cause of Lower Urinary Tract Symptoms (LUTS). The use of anti-inflammatory agents such as steroids, cyclooxygenase-2 (COX-2) and phytotherapics have been investigated as forms of treatment for various prostate diseases. Recent evidence has demonstrated that PDE5 inhibitors (PDE5Is) improve symptoms of BPH/LUTS, possibly as a result of the relaxing of the smooth muscle fibers of the bladder and prostate by NO/cGMPc signaling, or by improving RhoA/Rho-kinase (ROCK), and reduction of the hyperactivity of the autonomic nervous system. However, some results have suggested that besides vasodilatation and their anti-proliferative effect, PDE5Is exert a direct anti-inflammatory effect, by raising cGMP. Given that inflammation is major factor in benign prostatic hyperplasia (BPH) progression, PDE5Is could act also restore prostatic function as they act as potent anti-inflammatory drugs. This review aims to provide a comprehensive summary of the use of phosphodiesterase-5 inhibitors to treat prostatic inflammation.

Clinically and Statistically Significant Changes Seen in Sham Surgery Arms of Randomized, Controlled Benign Prostatic Hyperplasia Surgery Trials

PURPOSE

Medication trials frequently involve a placebo arm to more fairly assess the efficacy of the study drug. However, benign prostatic hyperplasia surgery trials rarely include a sham surgery group due to the inherent risks associated with simulating treatment in these patients. As a result the placebo response to sham surgery for benign prostatic hyperplasia is largely unknown.

MATERIALS AND METHODS

We systematically reviewed the available literature to look for randomized, controlled trials involving endoscopic or intraprostatic injection benign prostatic hyperplasia treatments that included a sham surgical arm from January 1990 to February 2015. Studies that included an objective symptom questionnaire and maximum urinary flow at 3 months were included. Results were analyzed together with weighting based on study sample size.

RESULTS

The initial search yielded a total of 1,998 potential studies. After reviewing abstracts and full text articles 14 randomized, controlled trials were included in some part. An average decrease from 22.3 to 16.7 (-27%) was seen in studies of the AUASS (American Urological Association symptom score) 3 months after a sham endoscopic procedure (p=0.0003) with an increase in maximum urinary flow of 1.3 ml per second (14%, p=0.001) at 3 months. Prostate injection based studies at 3 months were similar with a decrease from 21.3 to 15.7 (-26%, p<0.001). Maximum urinary flow increased by 2.0 ml per second (23%, p=0.043).

CONCLUSIONS

Sham controlled endoscopic and injection benign prostatic hyperplasia interventions demonstrate a considerable and statistically significant change in symptom scores and maximum urinary flow, which is comparable to the response seen in medication trials. Future uncontrolled benign prostatic hyperplasia surgical trials should consider these findings when interpreting outcomes.

Comparative Effectiveness and Safety of Monodrug Therapies for Lower Urinary Tract Symptoms Associated With Benign Prostatic Hyperplasia: A Network Meta-analysis

A wide array of drugs are available for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH), but the evidence for the comparative effectiveness is controversial.The objective of this study is to evaluate the comparative effectiveness and safety of monodrug therapies for BPH.Data sources are MEDLINE, EMBASE, and the Cochrane Library.We included randomized controlled trials that compared α-blockers, 5-alpha reductase inhibitors (5ARIs), muscarinic receptor antagonists (MRAs), phosphodiesterase-5 inhibitor (PDE5-Is), or placebo for the treatment of BPH.Comparative effectiveness and safety were pooled by both traditional meta-analysis and network meta-analysis. Summary effect size was calculated as mean difference (MD) and relative risk (RR), together with the 95% confidence intervals (CIs).This study included 58,548 participants from 124 trials in total. When compared with placebo, α-blockers, 5ARIs, and PDE5-Is reduced International Prostate Symptom Score (IPSS) by -1.35 to -3.67 points and increased peak urinary flow rate (PUF) by -0.02 to 1.95 mL/s, with doxazosin (IPSS: MD, -3.67[-4.33 to -3.02]; PUF: MD, 1.95[1.61 to 2.30]) and terazosin (IPSS: MD, -3.37 [-4.24 to -2.50]; PUF: MD, 1.21[0.74 to 1.66]) showing the greatest improvement. The improvement in the IPSS was comparable among tamsulosin, alfuzosin, naftopidil, silodosin, dutasteride, sildenafil, vardenafil, and tadalafil. The incidence of total adverse events and withdraws due to adverse events were generally comparable among various agents.In conclusion, α-blockers, 5ARIs, and PDE5-Is are effective for BPH, with doxazosin and terazosin appearing to be the most effective agents. Drug therapies for BPH are generally safe and well-tolerated, with no major difference regarding the overall safety profile.

Efficacy and Safety of Plasmakinetic Resection of the Prostate in Patients with a Prostate Gland Larger than 80 cc: 30-Month Follow-Up Results

PURPOSE

This study aimed to evaluate the efficacy and safety of transurethral plasmakinetic resection of the prostate (PKRP) for the treatment of patients with benign prostatic hyperplasia (BPH) in men with prostate volume >80 cc.

PATIENTS AND METHODS

From January 2010 to December 2011, 120 patients were included in our study; among these patients, 66 had prostate sizes of 80 cc to 100 cc and 54 had prostate sizes >100 cc. Pre-, peri- and postoperative evaluations were performed.

RESULTS

The mean operative duration of PKRP was 112 minutes, and the mean resected tissue weight was 60.01 g. Hemoglobin level decreased by 0.65±0.52 g/dL, and serum sodium content decreased by 0.06±2.62 mmol/L. The mean catheterization time was 83.05 hours, and the mean hospital stay was 12.47 days. The short follow-up time (30 months) demonstrated significant improvement in International Prostate Symptom Score, quality of life, and postvoid residual volume compared with preoperative characteristics. One patient underwent reoperation because of a blood clot in the bladder. Twelve patients complained of retrograde ejaculation. No patient experienced urinary incontinence.

CONCLUSIONS

PKRP is safe and efficacious for men with BPH who have a large prostate (volume >80 cc).

Tamsulosin combined with solifenacin versus tamsulosin monotherapy for male lower urinary tract symptoms: a meta-analysis

OBJECTIVE

To evaluate the efficacy and safety of tamsulosin and solifenacin combination therapy compared with tamsulosin monotherapy for male lower urinary tract symptoms (LUTS).

METHODS

We identified all eligible studies that compared tamsulosin and solifenacin combination therapy with tamsulosin monotherapy for male LUTS (up to January 2015). The fixed- or random-effects model was selected depending on the proportion of heterogeneity.

RESULTS

Seven articles were identified as eligible for this meta-analysis, with a total of 3063 participants. Synthetic data showed combination therapy had significant improvements in Storage International Prostate Symptom Score (WMD = -0.60; 95% CI: -0.81 to -0.38, P < 0.0001), quality of life (WMD = -0.23; 95% CI: -0.34 to -0.11, P < 0.0001), micturitions per 24 hours (WMD = -0.70; 95% CI: -0.86 to -0.55, P < 0.0001) and urgency episodes per 24 hours (WMD = -0.26; 95% CI: -0.48 to -0.05, P = 0.018). The incidence of adverse effects in the tamsulosin and solifenacin combined therapy group (30.82%) was similar to the tamsulosin monotherapy group (25.75%). Acute urinary retention was seldom reported in the studies and no clinically significant changes regarding Qmax were showed in our meta-analysis.

CONCLUSIONS

Tamsulosin and solifenacin combination therapy may be a reasonable option for male LUTS patients, especially for those who have significant storage symptoms. However, PVR should be measured during treatment to assess the increase in PVR or the incidence of AUR.