Association between vitamin D receptor gene polymorphisms and genetic susceptibility to benign prostatic hyperplasia: A systematic review and meta-analysis

BACKGROUND

Benign prostatic hyperplasia (BPH) is one of the global public health challenges due to the complexity of its mechanisms of occurrence. Many studies have suggested that vitamin D receptor gene polymorphisms are associated with BPH susceptibility. Still, their conflicting findings need to be analyzed in aggregate to gain a better understanding.

METHODS

We identified 10 trials involving 1539 BPH cases and 1915 controls through a systematic search of Embase using, data obtained from the Web of Science, PubMed, and China Knowledge Network databases as of December 31, 2021. A meta-analysis was performed to investigate the association between 4 constant polymorphisms of this associated vitamin D receptor gene (Fok-1, Bsm-1, Taq-1, and Apa-1) and BPH risk.

RESULTS

In the overall population analysis, a significant positive association with BPH risk was found only in the Taq-1 variant (P < .001). Of these, the pure-hybrid model (95% confidence interval [CI] = 1.384-3.196), the heterozygous model (95% CI = 1.207-2.021), the dominant model (95% CI = 1.312-2.133) and the allelic inheritance model (95% CI = 1.205-1.730) showed low heterogeneity. In subtype analyses, Bsm-1 variants showed a significant association with BPH risk for both the recessive (95% CI = 0.100-0.943, P = .039) and over-dominant (95% CI = 1.553-3.100, P = 0) models in the Caucasian population, and for the recessive (95% CI = 1.242-3.283, P = .039) and over-dominant (95% CI = 0.281-0.680, P = 0) models in the Asian population. In addition, a high degree of heterogeneity was found in the subgroup analysis of the association between Fok-1 variants and BPH risk.

CONCLUSION

Overall, there is an association between vitamin D receptor polymorphisms and BPH risk. Identification of BPH susceptibility by vitamin D receptor gene polymorphisms has potential.

A Prospective, Randomized Study Comparing the Outcome After Thulium Laser Enucleation of the Prostate with Conventional Monopolar TURP for the Treatment of Symptomatic Benign Prostatic Hyperplasia

OBJECTIVE

This is a prospective randomized study with the aim of comparing (thulium laser enucleation of the prostate (ThuLEP) and transurethral resection of the prostate (TURP) for benign prostatic hyperplasia (BPH) treatment.

METHODS

Patients are assessed preoperatively and up to 6 months postoperatively. International Prostate Symptom Score (IPSS), quality of life (QoL), maximum urinary flow rates (Qmax), international index of erectile function-5 (IIEF-5) and post-void residual volume (PVR) are collected on each follow-up.

RESULTS

In comparison to TURP, the ThuLEP group has significantly less need for catheter traction and less need for postoperative irrigation. The operative time is significantly higher in ThuLEP compared to TURP. ThuLEP is significantly superior to TURP in terms of early catheter removal, less drop in haemoglobin, less fall in serum sodium level, and early hospital discharge. ThuLEP and TURP resulted in a significant improvement from baseline in terms of IPSS, PVR, Qmax, and QoL, but there was no significant difference between the 2 groups. The IIEF-5 is the same as the baseline in both groups. Early and late complications are also comparable.

CONCLUSION

The ThuLEP outperforms TURP in terms of blood loss, significantly less need for postoperative catheter traction, bladder irrigations, early catheter removal, and less hospital stay. Transurethral resection of the prostate takes longer operative time in the early stages of experience. The results of both surgeries are comparable in terms of PVR, Qmax, and subjective scoring systems (IPSS, QoL). Transurethral resection of the prostate is a safe and efficient BPH treatment method comparable to the monopolar TURP.

Association of Benign Prostatic Hyperplasia With Multimorbidity Among Older Adults: Insights From the Longitudinal Ageing Study in India (LASI), First Wave

Introduction Population ageing is expected to be accompanied by an increase in multi-morbidity, i.e. the co-occurrence of multiple chronic conditions simultaneously. Benign prostatic hyperplasia (BPH) is a non-malignant disease prevalent in ageing men. Both BPH and multi-morbidity are known to have a significant impact on quality of life. The objective of this study was to determine the association between BPH and multimorbidity among older adults and the elderly population in India. Methods This is an analytical cross-sectional study involving secondary data from the nationally representative Longitudinal Ageing Study in India (LASI) Wave I 2017-18. Multivariable logistic regression analysis was conducted to study the association between BPH and multimorbidity while accounting for other associated factors. Results Compared to those having no co-morbidities, the odds of having BPH increased with the increasing number of co-morbidities. Those with at least two co-morbidities were twice as likely (aOR=2.19; 95%CI 1.78-2.72), and those with at least four co-morbidities were almost six times as likely (aOR=5.78; 95%CI 2-16.72) to have BPH as compared to those with no co-morbidities. The association was stronger among males >60 years. Conclusion Self-reported benign prostatic hyperplasia was found to be strongly associated with multi-morbidity. The need of the hour is the inclusion of BPH within the framework of a national health programme. Health technology assessment of high-risk screening strategies for BPH may be conducted among patients with multimorbidity. Research into the impact on the quality of life of those affected by both BPH and multimorbidity will help highlight this as a priority problem for decision-makers.

Lipoxygenase-12 Levels and Biochemical Parameters in Iraqi Patients With Type 2 Diabetes With and Without Benign Prostatic Hyperplasia

Background Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia caused by a defect in the secretion or action or both of insulin. It has a complex pathogenesis. Benign prostatic hyperplasia (BPH) refers to an increase in the size of the prostate; it is one of the most common health problems in men that manifests with age. Lipoxygenase-12 (Lipox-12) is one of the enzymes in the Lipox 12/15 family, which plays a major role in catalyzing a variety of polyunsaturated fatty acids (PUFAs) that are capable of producing different metabolites. Lipox-12 has a significant effect on arachidonic acid metabolism, with PUFA, a pro- and anti-inflammatory mediator, as one of the enzyme isoforms. It also plays a major role in modulating inflammation at multiple checkpoints as diabetes progresses. The present study aims to measure Lipox-12 levels in patients with DM type 2 (DM2) and patients with DM2 + BPH. Methodology This study was conducted in Musayyib General Hospital, south of Baghdad, where a clinical examination was performed on 50 samples from controls (healthy subjects), 50 patients with DM2, and 50 patients with DM2 + BPH after taking each patient's history. The examinations performed included fasting blood sugar (FBS), hemoglobin A1c (HbA1c), prostate-specific antigen (PSA), triglycerides (TG), cholesterol (Chol), and Lipox-12. Results The results showed that both the DM2 and DM2 + BPH groups had higher FBS, HbA1c, TG, and Chol levels than healthy subjects; in contrast, Lipox-12 levels were the lowest in the DM2 group (sensitivity = 79% and specificity = 81%) but higher in the DM2 + BPH group (sensitivity = 80%; specificity = 82%) compared to the control group. Conclusions Lipox-12 had a high sensitivity and specificity in the DM2 and DM2 + BPH groups compared to the control group, and in both cases, it was used to monitor and diagnose DM2 and BPH.

The effect of bladder function on the efficacy of transurethral prostatectomy in patients with benign prostatic hyperplasia: a retrospective, single-center study

We investigated the impact and predictive value of bladder function in patients with benign prostatic hyperplasia (BPH) on the efficacy of transurethral prostatectomy. Symptomatic, imaging, and urodynamic data of patients who underwent transurethral prostatectomy at West China Hospital of Sichuan University (Chengdu, China) from July 2019 to December 2021 were collected. Follow-up data included the quality of life (QoL), International Prostate Symptom Score (IPSS), and IPSS storage and voiding (IPSS-s and IPSS-v). Moreover, urinary creatinine (Cr), nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and prostaglandin estradiol (PGE2) were measured in 30 patients with BPH and 30 healthy participants. Perioperative indicators were determined by subgroup analyses and receiver operating characteristic (ROC) curve analysis. Among the 313 patients with BPH included, patients with severe micturition problems had more improvements but higher micturition grades postoperatively than those with moderate symptoms. Similarly, good bladder sensation, compliance, and detrusor contractility (DC) were predictors of low postoperative IPSS and QoL. The urinary concentrations of BDNF/Cr, NGF/Cr, and PGE2/Cr in patients were significantly higher than those in healthy participants (all P < 0.001). After evaluation, only DC was significantly related to both urinary indicators and postoperative recovery of patients. Patients with good DC, as predicted by urinary indicators, had lower IPSS and IPSS-v than those with reduced DC at the 1st month postoperatively (both P < 0.05). In summary, patients with impaired bladder function had poor recovery. The combined levels of urinary BDNF/Cr, NGF/Cr, and PGE2/Cr in patients with BPH may be valid predictors of preoperative bladder function and postoperative recovery.

Impact of Duration of Catheterization on the Success Rate of Trial Without Catheter in Acute Urinary Retention Due to Benign Prostatic Enlargement

BACKGROUND

The most common cause of acute urinary retention in men over 50 is benign prostate enlargement (BPE). Following the urethral catheterization, a trial without a catheter (TWOC) under the cover of alpha-blockers is given. The timing of TWOC varies from Day 3 to Day 7 of the retention episode. There is a need to study the improvement in the success rate of TWOC with the increasing number of days of catheterization.

OBJECTIVE

To measure the success rate of TWOC in acute urinary retention due to benign prostatic enlargement with increasing days of catheterization.

METHOD

The study was conducted in Social Security Teaching Hospital Lahore. Patients who presented with acute urinary retention due to benign prostatic enlargement were catheterized and given alpha-blockers. The patients were divided into two groups, one group having TWOC after three days and the other having TWOC after seven days. The success rate of TWOC was calculated and compared in the two groups. All patients included in the study had the first episode of acute retention with a moderately enlarged prostate and no element of second pathology or neurological deficit.

RESULTS

A total of 48 patients were included in the study, divided into two groups of 24 patients each. In the first group who underwent TWOC after seven days of catheterization, 15 out of 24 patients had successful TWOC with a success rate of 62.5%. In the second group of 24 patients, who had TWOC after three days of catheterization, only 11 patients had successful TWOC with a success rate of 45.8%.

CONCLUSION

There was a marked improvement in the success rate of TWOC with increasing days of catheterization after an acute retention episode, secondary to BPE.

Comprehensive Review on Current Controversies and Debate in Prostate Artery Embolization

Prostate artery embolization is emerging as one of the most effective therapies amidst a new era of mini- mally invasive benign prostate hyperplasia treatment and technology. However, several current controver- sies remain unanswered which could impact the widespread adoption of this novel and unique transarterial(rather than transurethral) intervention. This is reflected in the differences between the UK (NICE), European (EAU), and American (AUA) guidelines, the latter of which only recommends the use of prostate arteryembolization in a clinical trial setting. The main issues include questions over the duration of symptom response, cost-effectiveness, mechanism of action, patient selection, and other procedural technical consid- erations. These factors are the most pressing faced by proponents of prostate artery embolization, and we seek to highlight why their resolution is important to ensure men with benign prostate hyperplasia seeking a minimally invasive solution are optimally informed and most effectively managed.

Recent advances in UroLift: A comprehensive overview

OBJECTIVE

Recent years have seen a steep rise in minimally invasive surgical therapy (MIST) for benign prostate hyperplasia (BPH). Prostatic urethral lift (UroLift) is a mechanical intervention aimed at reducing lower urinary tract symptoms, which affect patients with BPH.

MATERIAL AND METHODS

A narrative synthesis of all studies regarding UroLift is performed over the last decade, evaluating its impact on International Prostate Symptom Score (IPSS), quality of life (QoL), Qmax, Benign Prostate Hypertrophy Impact Index, and sexual health metrics.

RESULTS

The studies included have demonstrated significant improvements in the objective parameters measured. UroLift has a low side-effect profile and is comparable to transurethral resection of the prostate in QoL changes and is superior with respect to recovery time and ejaculatory function.

CONCLUSION

Our findings suggest that UroLift may be an appropriate treatment for individuals undergoing treatment for BPH who are concerned with sexual and ejaculatory functions. More studies are needed to determine who is eligible for UroLift, as well as the long-term impact of UroLift on individuals with BPH.

Outcomes of bipolar TURP compared to monopolar TURP: A comprehensive literature review

OBJECTIVE

Transurethral resection of the prostate (TURP) is the commonest surgical procedure for the treatment of benign prostatic obstruction (BPO). Bipolar-TURP (BTURP) is being increasingly used as compared to the long-established Monopolar TURP (MTURP). In this systematic review, we compared the outcomes of BTURP vs MTURP.

MATERIAL AND METHODS

A systematic review was conducted using PubMed, EMBASE, Scopus, Google Scholar, and the Cochrane library using relevant search terms from inception of databases till June 2020. Using PRISMA methodology, 18 randomized control trials were reviewed comparing MTURP vs BTURP with a total of 8,393 patients.

RESULTS

A significant drop in serum sodium was seen in four studies in MTURP vs BTURP and while there was zero incidence of TUR syndrome in BTURP group, there were 1-16 episodes of TUR syndrome across studies in the MTURP group. A significant fall in hematocrit was seen in three of nine studies with MTURP and one with a significant difference in blood transfusion rates. There were no significant differences in the incidence of clot retention across the studies with 1-5 cases in BTURP group vs 2-12 cases in MTURP group. There were no significant differences related to the duration of catheterization, operative time, resection volume, length of stay, quality of life, postoperative urethral stricture, and sexual function.

CONCLUSION

Although both BTURP and MTURP improve urinary symptoms, BTURP is associated with less risk of hyponatremia, TUR syndrome, and blood loss compared to MTURP. There seems to be no significant difference in length of stay, urethral stricture, quality of life, and operative duration.

Sloughing Prostatic Tissue, a Rare Complication Post Rezum Therapy: A Case Report

Benign prostatic hyperplasia (BPH) is the most prevalent urological disease in men that leads to lower urinary tract symptoms (LUTS). The clinical presentation is, most likely, obstructive symptoms such as intermittency, hesitancy and poor stream, due to the obstructive nature of the pathology. BPH treatment approach varies. However, they can be divided into two main approaches which are non-surgical and surgical. Non-surgical methods usually started first, such as lifestyle modifications, watchful waiting, and medications. Hence, surgical intervention remains the mainstay of treatment to relieve clinical symptoms. Although transurethral resection of the prostate (TURP) is the gold standard, management is shifting towards minimally invasive surgeries such as Rezūm due to its good outcome and fewer adverse effects. We present a case of prostatic tissue sloughing, a rare complication post Rezūm system therapy in a 50-year-old male.

Endoscopic enucleation vs endoscopic vaporization procedures for benign prostatic hyperplasia: how should we choose: A protocol for systematic review and meta-analysis

OBJECTIVE

To assess the safety and efficacy of different endoscopic procedures of the prostate techniques, by comparing endoscopic enucleation (EEP) and endoscopic vaporization procedures (EVP) of the prostate; and laser enucleation procedures (L-EEP) vs laser vaporization procedures (L-EVP) surgeries for benign prostatic hyperplasia.

METHODS

A systematic literature review was performed in December 2019 using PubMed, Embase and the Cochrane Library to identify relevant studies. Two analyses were carried out: (1) EEP vs EVP; and (2) L-EEP vs L-EVP. Efficacy and safety were evaluated using perioperative data, functional outcomes, including maximum urinary flow rate (Qmax), quality of life (QoL), international prostate symptom score (IPSS), postvoiding residual urine volume (PRV), and rate of complications. Meta-analyses were conducted using RevMan5.3.

RESULTS

Sixteen studies (4907 patients) evaluated EEP vs EVP, and 12 of them (4392 patients) evaluated L-EEP vs L-EVP. EEP showed improved functional outcomes compared with EVP. EEP was always presented a better Qmax at various follow-up times. EEP also associated with a reduced PRV and IPSS at 12 months postsurgery, an increased Qmax, and reduced IPSS and QoL score at both 24 and 36 months postsurgery. In addition, EEP was associated with less total energy utilized and retreatment for residual adenoma, but a longer catheterization time. Among other outcomes, there was no significant difference. L-EEP favors total energy used, retreatment for residual adenoma, and functional outcomes. L-EEP was associated with reduced PRV at 1, 6, and 12 months postsurgery, a greater Qmax at 6 and 12 months postsurgery, a lower IPSS at 12 months postsurgery, and higher Qmax and lower IPSS and QoL scores at 24 and 36 months postsurgery. However, there was no difference at 3 months postsurgery. No significant differences were observed for other perioperative data and complications.

CONCLUSIONS

Both EEP and EVP displayed sufficient efficacy and safety for treating benign prostatic hyperplasia. EEP and L-EEP were favored in perioperative data, rate of complications, and functional outcomes. However, the clinical significance of those statistical differences was unclear. Hence, higher-quality randomized controlled trials may be needed to provide a clear algorithm.

MRI characterization of the dynamic effects of 5α-reductase inhibitors on prostate zonal volumes

INTRODUCTION

Prior studies of volumetric effects of 5α-reductase inhibitors (5ARIs) on the prostate have used transrectal ultrasound which provides poor differentiation of prostatic zones. We utilized high-resolution prostate MRI to evaluate the true dynamic effects of 5ARI in men who underwent multiple MRIs.

MATERIALS AND METHODS

A retrospective study of patients who underwent serial 3.0 Tesla prostate MRI from 2007 to 2012 and were treated with 5ARI were studied. Nineteen patients who had a baseline MRI prior to 5ARI initiation and subsequent MRI follow up were selected. A randomly selected group of 40 patients who had not received any form of therapy was selected as the control cohort. Total prostate volume (TPV), transition zone volume (TZV), and peripheral zone volume (PZV) were calculated using 3D reconstructions and prostate segmentation from T2-weighted MRI. Changes in volumes were correlated with the duration of treatment using linear regression analysis.

RESULTS

Following over 2 years of treatment, 5ARI decreased TPV significantly (16.7%, p < 0.0001). There were similar decreases in TZV (7.5%, p < 0.001) and PZV (27.4%, p = 0.0002) from baseline. In the control group, TPV and TZV increased (p < 0.0001) while PZV remained stable. When adjusted for the natural growth of prostate zonal volume dynamics seen in the control cohort, approximately 60% of the reduction of the TPV from 5ARI resulted from changes in the TZV and 40% of the reduction from changes in the PZV.

CONCLUSIONS

3.0 Tesla MRI characterizations of the dynamic effects of 5ARI on prostate zonal volumes demonstrate significant decreases in TPV, TZV, and PZV. 5ARI blocks the natural growth of TZV as men age and decreases both TZV and PZV below their baselines. As imaging technology improves, prostate MRI allows for more accurate assessment of drug effects on dynamic prostate volumes.

National-wide data on the treatment of BPH in Korea

The healthcare system in Korea provides coverage to all the people who are residing in Korea, so the data of the Korea healthcare system are national-wide and relatively accurate. We obtained the recent 5-year data (2004-2008) on the treatment of BPH from the national health insurance system. We tried to determine the trends or changes of BPH treatments in Korea. Over 3.8 million men visited clinics and were prescribed one or more BPH medications, and more than 44 000 men underwent surgical treatment during 2004-2008. Compared with the year 2004, two times the patients were prescribed BPH medications in 2008. With respect to the surgical treatment, the number of cases was increased 1.6 times in 2006 compared with the previous years. The most commonly used surgical option was TURP before 2006, but laser therapy was carried out as much as TURP in 2006 and in the following years. The relative risk of laser therapy in the 50 s is 1.53 (95% CI is 1.47-1.59). In conclusion, our national-wide data for the Korean BPH patients show that these patients' medical treatment increased during the 5 years from 2004 to 2008. Laser treatment had increased and it might replace TURP in several years.

Benign Prostatic Hyperplasia and Male Lower Urinary Tract Symptoms: Epidemiology and Risk Factors

The epidemiology of benign prostatic hyperplasia (BPH) and male lower urinary tract symptoms (LUTS) has evolved considerably during the past several years. The term LUTS describes a distinct phenotype and allows for a broad epidemiologic description of urinary symptoms at a population level. Although it is becoming the preferred term for studying urinary symptoms in populations, LUTS remains interconnected with BPH in the literature. The incidence and prevalence of BPH and LUTS are increasing rapidly as the US population ages. BPH and LUTS are associated with serious medical morbidities, an increased risk of falls, depression, diminished health-related quality of life, and billions of dollars in annual health care costs. Although age and genetics play important roles in the etiology of BPH and LUTS, recent insights at the population level have revealed that modifiable risk factors are likely key components as well. Serum dihydrotestosterone, obesity, elevated fasting glucose, diabetes, fat and red meat intake, and inflammation increase the risk; vegetables, regular alcohol consumption, exercise, and NSAIDs decrease the risk.

How large is too large?

BPH remains one of the most common diseases that the urologist has to manage. The last decade brought numerous new techniques, aiming to improve the minimally invasive approach to BPH, but, for the moment, none had changed the place of TURP as the gold standard treatment for medium sized prostates. Based on a large personal experience, the authors present a study in which TURP is used for prostates over 80 ml, the cutoff point set by the guidelines of the European Association of Urology. The rationale for this study is that many situations require minimally invasive treatment, based on the express request of the patient, other conditions that makes open surgery very difficult or impossible, or the need for a quick discharge in an overcrowded service. The aim of the study was to prove that TURP is safe and effective even in larger prostates. The technique used is basically the classic one, with minor tactical alterations in some cases. Some cases required a two-stage approach, but offered good functional results after the first stage. The results proved that, with a good technique, a skilled urologist might achieve the same results by using TURP or open surgery for large sized prostates.

Monocyte chemotactic protein-1 (MCP-1/CCL2) is associated with prostatic growth dysregulation and benign prostatic hyperplasia

BACKGROUND

Chronic inflammation is commonly observed in benign prostate hyperplasia (BPH), and prostate tissue often contains increased inflammatory infiltrates, including T cells and macrophages. Cytokines are not only key mediators of inflammation but may also play important roles in the initiation and progression of BPH.

METHODS

In order to determine what cytokines might be involved in prostatic enlargement, expressed prostatic secretions (EPS) from ex vivo prostates were analyzed by human cytokine antibody microarray and ELISA. Prostate epithelial cells (PrEC) and prostate stromal cells (PrSC) were used for ELISA, proliferation, and Western blot assays.

RESULTS

Monocyte chemotactic protein-1 (MCP-1/CCL2) was one of the most elevated proteins in secretions from large prostate glands. PrSC were found to secrete MCP-1; Western blotting showed that both PrSC and PrEC express the MCP-1 receptor CCR2 which by RT-PCR was the CCR2b isoform. Proliferation assays showed that MCP-1 stimulates the proliferation of PrEC, but not PrSC, and that a specific MCP-1 antagonist (RS102895) suppressed this effect. Conditioned medium from PrSC stimulated the proliferation of PrEC as well, an effect completely inhibited by both RS102895 and a neutralizing anti-MCP-1 monoclonal antibody. The inflammatory cytokines interleukin (IL)-1 beta, interferon-gamma, and IL-2 enhanced the secretion of MCP-1 from PrEC and PrSC. In addition, MCP-1 levels in EPS correlated with mRNA levels of the macrophage marker CD68 in the same secretions.

CONCLUSIONS

The cytokine MCP-1, of apparent prostatic stromal cell origin, may play an important role in prostatic enlargement and BPH, and is a candidate biomarker for these pathologic processes.

Leukocytic promotion of prostate cellular proliferation

BACKGROUND

Histological evidence of pervasive inflammatory infiltrate has been noted in both benign prostatic hyperplasia/hypertrophy (BPH) and prostate cancer (PCa). Cytokines known to attract particular leukocyte subsets are secreted from prostatic stroma consequent to aging and also from malignant prostate epithelium. Therefore, we hypothesized that leukocytes associated with either acute or chronic inflammation attracted to the prostate consequent to aging or tumorigenesis may promote the abnormal cellular proliferation associated with BPH and PCa.

METHODS

An in vitro system designed to mimic the human prostatic microenvironment incorporating prostatic stroma (primary and immortalized prostate stromal fibroblasts), epithelium (N15C6, BPH-1, LNCaP, and PC3 cells), and inflammatory infiltrate (HL-60 cells, HH, and Molt-3 T-lymphocytes) was developed. Modified Boyden chamber assays were used to test the ability of prostate stromal and epithelial cells to attract leukocytes and to test the effect of leukocytes on prostate cellular proliferation. Antibody arrays were used to identify leukocyte-secreted cytokines mediating prostate cellular proliferation.

RESULTS

Leukocytic cells migrated towards both prostate stromal and epithelial cells. CD4+ T-lymphocytes promoted the proliferation of both transformed and non-transformed prostate epithelial cell lines tested, whereas CD8+ T-lymphocytes as well as dHL-60M macrophagic and dHL-60N neutrophilic cells selectively promoted the proliferation of PCa cells.

CONCLUSIONS

The results of these studies show that inflammatory cells can be attracted to the prostate tissue microenvironment and can selectively promote the proliferation of non-transformed or transformed prostate epithelial cells, and are consistent with differential role(s) for inflammatory infiltrate in the etiologies of benign and malignant proliferative disease in the prostate.

Inflammation in benign prostatic hyperplasia: a 282 patients' immunohistochemical analysis

INTRODUCTION AND OBJECTIVES

Prostatic inflammation could be a key component in prostate enlargement and benign prostatic hyperplasia (BPH) progression. Our aim was to characterize inflammatory cells infiltrate within BPH tissue and to correlate inflammation and clinical data.

MATERIAL AND METHODS

Inflammation was profiled on three clinical outcome tissue microarrays (TMAs), including 282 patients treated by surgery for a complicated and/or symptomatic BPH. Inflammation score was defined by combining six cytological parameters and five markers on immunohistochemistry (IHC). Cytological parameters were lymphocytes, macrophages, and polynuclears leukocytes infiltrates, and three glandular aspect modifications: glandular atrophy, glandular destruction, and tissue fibrosis. IHC markers were CD3, CD4, and CD8 decorating T-lymphocytes, CD20 decorating B-lymphocytes, and CD163 decorating macrophages.

RESULTS

The majority of patients had inflammatory cells infiltrating BPH tissues: 81% had T-lymphocytes markers (CD3), 52% had B-lymphocytes markers (CD20), and 82% had macrophages markers (CD163). IPSS score (21 vs. 12; P = 0.02) and prostate volume (77 cm(3) vs. 62 cm(3); P = 0.002) were significantly higher in patients with high-grade prostatic inflammation.

CONCLUSION

We characterized inflammatory cells infiltrate in a large cohort of surgically treated BPH specimens. The role of inflammation in BPH development was highlighted by the strong correlation between histological inflammation, IPSS, and prostate volume. Prostate enlargement due to chronic inflammatory process may progressively conduce to BPH progression. Therefore, inflammation is a therapeutic target for BPH.

The expression of androgen-responsive genes is up-regulated in the epithelia of benign prostatic hyperplasia

BACKGROUND

Benign prostatic hyperplasia (BPH) is one of the most common diseases among aging men in the United States. In addition to aging, the presence of androgens is another major risk factor in BPH development. However, whether androgen signaling is altered in BPH remains unclear. To determine androgen signaling in BPH, we characterized the expression of four different androgen-responsive genes, Eaf2/U19, ELL2, FKBP5, and PSA, in BPH and adjacent normal glandular epithelial cells.

METHODS

A set of 17 BPH specimens were resected from patients over 60 years of age with clinical symptoms of BPH. Laser-capture microdissection (LCM) was used to isolate glandular epithelial cells from BPH areas and adjacent normal areas, separately. LCM isolated cells from individual specimens were lysed and RNA isolation, reverse transcription, and real-time PCR were performed using CellsDirect One-Step qRT-PCR Kit (Invitrogen, Carlsbad, CA).

RESULTS

All of the assayed genes displayed increased expression, from approximately 2- to approximately 6-fold, in BPH as compared to the adjacent normal epithelial cells. We also generated a composite androgen response index based on the expression levels of the four genes, which provides a reliable readout for overall androgen action. Our study showed that the composite androgen response index in BPH is approximately 4-fold as compared to that in the adjacent normal tissues.

CONCLUSIONS

Androgen signaling is significantly elevated in BPH relative to the adjacent normal prostate. Understanding the mechanisms causing elevated androgen signaling may lead to novel approaches for prevention and/or treatment of BPH.

Intraprostatic botulinum toxin injection in patients with benign prostatic enlargement

Histological evidence of benign prostatic hyperplasia (BPH) exceeded 50% in men over 50 years of age and rose to 75% as men entered the eighth decade. Therapeutic options for BPH generally fall into one of the three categories: watchful waiting, medical treatment and surgery. Excluding watchful waiting, the other forms of intervention directed at modifying the physiologic effects of BPH with or without directly altering the prostatic mass or its configuration come with varying effectiveness and risk. Botulinum toxin (BTX-A) produce inhibition of acethylcholine release at the neuromuscular junction causes paralyzing effects and atrophy of striated as well as the smooth muscle fiber. BTX-A also causes inhibitory effects on the ganglionic and post-ganglionic fibres of autonomic nervous system inducing diffuse atrophy and apoptosis of nasal and prostate glands. Clinical series demonstrates efficacy of BTX-A in alleviating symptoms induced by BPH. Larger randomized clinical trials studies are necessary in order to identify the mechanisms by which BTX-A affects the prostate, the ideal dose and the duration of effect. BTX-A injected into prostate appears safe and effective.

A prospective randomized study comparing alfuzosin and tamsulosin in the management of patients suffering from acute urinary retention caused by benign prostatic hyperplasia

Objective : Prospective randomized study to compare the efficacy and safety of alfuzosin and tamsulosin in patients suffering from acute urinary retention caused by benign prostatic hyperplasia (BPH). Methods : Patients with acute urinary retention (AUR) due to BPH (total 150) were catheterized and randomized into three groups: Group A: alfuzosin 10 mg (50 patients), Group B: tamsulosin 0.4 mg (50 patients), Group C: placebo (50 patients). After three days, catheter was removed, and patients were put on trial without catheter (TWOC). Patients with successful TWOC were followed up for three months, taking into account the prostate symptom score (AUA Score), post-void residual urine volume (PVRV), and peak flow rate (PFR). ANOVA was used for statistical analysis. Results : Both group A (alfuzosin) and group B (tamsulosin) had similar results of TWOC (group A - 66%, group B - 70%), which were significantly superior than group C (placebo) - 36%. In follow up, three (9.1%) patients in group A, three (8.6%) patients in group B and eight (44.4%) patients in group C had retention of urine, requiring recatheterization. These patients were withdrawn from the study. After three months, alfuzosin- or tamsulosin-treated patients showed a significant decrease in AUA score and PVRV; and a significant increase in PFR as compared to placebo. Conclusions : TWOC was more successful in men treated with either alfuzosin or tamsulosin and the subsequent need for recatheterization was also reduced. Tamsulosin was comparable to alfuzosin in all respects, except a small but significant side effect of retrograde ejaculation.

Smoking and acute urinary retention: the Olmsted County study of urinary symptoms and health status among men

BACKGROUND

Previous reports have suggested an inverse relationship between smoking and surgery for benign prostatic hyperplasia (BPH). We hypothesized that acute urinary retention (AUR), an adverse outcome of this disease and indication for surgical treatment, may be related to smoking.

METHODS

Study subjects were randomly selected from Olmsted County men aged 40-79 identified through the Rochester Epidemiology Project. Of the 3,854 eligible men, 2,089 (54%) completed a questionnaire that included the American Urological Association Symptom Score and assessed smoking status. Community medical records were examined for occurrence of AUR with documented catheterization in the subsequent 10 years and occurrence of BPH surgery. Proportional hazard models were used to assess the relationship between baseline smoking status and subsequent retention.

RESULTS

In the 18,307 person-years of follow-up, 114 men had AUR. When compared to 727 never-smokers, there was a trend among the 336 current smokers to be at lower risk (Relative risk (RR) = 0.62, 95% Confidence Interval (CI) = 0.33, 1.18) whereas the 1,026 former smokers were at similar risk to non-smokers (RR = 1.0, 95%CI = 0.67, 1.46). Among men with moderate-severe symptoms at baseline, current smokers were at lower risk of retention compared to non-smokers (RR = 0.65, 95%CI = 0.22, 1.91) but the association approached the null among those with none-mild symptoms (RR = 0.91, 95% CI = 0.40, 2.06).

CONCLUSIONS

Community-dwelling men who currently smoke may be at a modestly reduced risk of AUR. The magnitude of this association is sufficiently small that it seems unlikely that this explains a sizable proportion of the inverse association between smoking and surgically treated BPH.

Prostate stem cells and benign prostatic hyperplasia

Pharmacological approaches are available to medically-managed patients with symptomatic BPH before surgical intervention is required. These include daily treatment with alpha-blockers and 5-alpha-reductase inhibitors alone or in combination. These medical approaches have two major problems. First, treatments are chronic and must be taken daily. Second, there are significant financial costs and quality of life issues for such chronic treatments. Is it possible to develop effective acute therapy for symptomatic BPH without the long-term androgen deprivation-induced side effects? Two seminal but rarely cited studies of Walsh [Peters, Walsh: N Engl J Med 317:599-604, 1987] and Coffey et al. [Sufrin et al.: Invest Urol 13:418-423, 1976], combined with the growing understanding of the stem cell organization of the prostate stromal (S) and epithelial (E) compartments and their reciprocal paracrine and autocrine interactions provides the rationale for an acute approach.The Walsh study documents that: (1) androgen deprivation disrupts the reciprocal interaction between the prostate S and E thereby decreasing the weight of both compartments and (2) once BPH develops, androgen deprivation does not decrease the number of stem cell units in either the S or E compartments since subsequent androgen restoration fully restores the enlarged gland. The Coffey study documents that acute androgen deprivation sensitizes S-E interactions to radiation induced disruptions so that following radiation, androgen restoration does not induce full gland regrowth. Therefore, effective therapy for symptomatic BPH should be achievable by acute treatment with reversible androgen deprivation for a limited period followed by a single dose of conformal external beam radiation before allowing the man to recovery his normal serum testosterone.

Alpha1-adrenoceptor subtypes and lower urinary tract symptoms

Benign prostatic hyperplasia (BPH) is a common cause of urinary outflow obstruction in aging men leading to lower urinary tract symptoms (LUTS). alpha(1)-Adrenoceptors (alpha(1)ARs) antagonists (blockers) have become a mainstay of LUTS treatment because they relax prostate smooth muscle and decrease urethral resistance, as well as relieving bladder LUTS symptoms. A review of key recent clinical trials suggests new insights into the role of specific alpha(1)AR subtypes in the treatment of LUTS.

Rethinking proteasome evolution: two novel bacterial proteasomes

The proteasome is a multisubunit structure that degrades proteins. Protein degradation is an essential component of regulation because proteins can become misfolded, damaged, or unnecessary. Proteasomes and their homologues vary greatly in complexity: from HslV (heat shock locus v), which is encoded by 1 gene in bacteria, to the eukaryotic 20S proteasome, which is encoded by more than 14 genes. Despite this variation in complexity, all the proteasomes are composed of homologous subunits. We searched 238 complete bacterial genomes for structures related to the proteasome and found evidence of two novel groups of bacterial proteasomes. The first, which we name Anbu, is sparsely distributed among cyanobacteria and proteobacteria. We hypothesize that Anbu must be very ancient because of its distribution within the cyanobacteria, and that it has been lost in many more recent species. We also present evidence for a fourth type of bacterial proteasome found in a few beta-proteobacteria, which we call beta-proteobacteria proteasome homologue (BPH). Sequence and structural analyses show that Anbu and BPH are both distinct from known bacterial proteasomes but have homologous structures. Anbu is encoded by one gene, so we postulate a duplication of Anbu created the 20S proteasome. Anbu's function appears to be related to transglutaminase activity, not the general stress response associated with HslV. We have found different combinations of Anbu, BPH, and HslV within these bacterial genomes, which raises questions about specialized protein degradation systems.

Serum dioxin, testosterone, and subsequent risk of benign prostatic hyperplasia: a prospective cohort study of Air Force veterans

BACKGROUND

Operation Ranch Hand veterans were involved in spraying herbicides, including Agent Orange, during the Vietnam War in 1962-1971; Agent Orange was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). It has been hypothesized that dioxins may be partially responsible for an increase of male reproductive tract disorders such as testicular cancer, cryptorchidism, and hypospadias.

OBJECTIVES

In this study, our objective was to assess the effect of serum TCDD concentration on the risk of development of benign prostatic hyperplasia (BPH) and on serum testosterone levels.

METHODS

This study was a longitudinal, prospective cohort study made up of U.S. Air Force veterans involved in Operation Ranch Hand. Other Air Force veterans who did not spray herbicides were included as comparisons. BPH was determined by medical record review and by medical examinations conducted during the study. Data were available for 971 Ranch Hand and 1,266 comparison veterans. We investigated the relationship between BPH and serum TCDD level using the Cox proportional hazards models adjusted for testosterone levels, body mass index (BMI), and the percentage change in BMI per year.

RESULTS

In univariate and multivariate analyses, the risk of BPH decreased with increasing serum TCDD in the comparison group. The multivariate risk ratio for BPH in the comparison group was 0.84 (95% confidence interval, 0.73-0.98). Excluding men with prostate cancer, inflammatory or other prostatic diseases did not substantially alter the association. Serum testosterone levels were inversely associated with serum TCDD levels in both Ranch Hand and comparison groups.

CONCLUSIONS

TCDD exposure at general population levels is associated with a decreasing risk of BPH with higher exposure levels. TCDD exposure is also negatively associated with serum testosterone levels.

Expanding the role of photoselective vaporization of the prostate

The use of the potassium-titanyl-phosphate (KTP) laser for the ablative treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH) has gained wide acceptance in the urologic community. The efficacy and safety of photoselective vaporization of the prostate using 60-W or 80-W KTP have been demonstrated in multiple trials, with significant impact on special high-risk surgical populations (ie, patients with large prostates and anticoagulated patients with multiple comorbidities) with symptomatic BPH. The high-power KTP laser technique has also shown encouraging results in the management of urethral strictures. With catheter removal, improvement in voiding may not immediately occur; however, with the efficient vaporization and limited coagulation necrosis that are routinely noted with high-power KTP applications, improvement may occur in as early as a few days to 1 week. Because of the superior surgical hemostasis associated with laser prostatectomy, no restrictions on physical activity are required after the procedure, even in the immediate postoperative period.

Direct effect of zinc on mitochondrial apoptogenesis in prostate cells

BACKGROUND

Prostate epithelial cells uniquely accumulate significantly higher levels of zinc than other mammalian cells. We previously showed that the accumulation of high intracellular zinc levels in specific prostate cells results in the induction of apoptosis and the inhibition of cell growth. The apoptotic effect is due to zinc induction of mitochondrial apoptogenesis. We now report additional studies that corroborate this effect of zinc and provide insight into the mechanism of this unique effect.

METHODS

The effect of exposure to physiological levels of zinc on apoptosis was determined for three human prostate cell lines (PC-3, BPH, and HPR-1). Zinc-induced apoptosis was identified by DNA fragmentation. The direct effect of zinc on isolated mitochondrial preparations from each cell line was determined. The mitochondrial release of cytochrome c was determined by Western blot.

RESULTS

Exposure to zinc induced apoptosis in PC-3 and BPH cells but not in HPR-1 cells. The zinc accumulation in PC-3 (4.3 +/- 0.3) and BPH (2.8 +/- 0.4) was higher than that in HPR-1 cells (1.8 +/- 0.1). The apoptotic effect of zinc on PC-3 cells could be observed as early as 4-6 hr of zinc treatment, and this effect was not reversible. The exposure of isolated mitochondria from PC-3 and BPH cells to zinc resulted in the release of cytochrome c; but zinc had no effect on mitochondria from HPR-1 cells.

CONCLUSIONS

Exposure to zinc induces apoptosis in PC-3 and BPH cells, which accumulate high intracellular levels of zinc, but not in HPR-1 cells, which do not accumulate high levels of zinc. Once initiated, the induction of apoptosis is not reversed by the removal of zinc, i.e., it is an irreversible process. The apoptogenic effect is due to a direct effect of zinc on mitochondria that results in the release of cytochrome c. The cell specificity of zinc induction of apoptogenesis is dependent on the ability of the cells to accumulate high levels of intracellular zinc and on the ability of the mitochondria to respond to the direct effect of zinc.

The picture of the prostatic lymphokine network is becoming increasingly complex

The immunology of the prostate has recently developed into a new field of research in urology. Although we do not yet understand why the leukocyte population increases, we know that most resected prostate tissue shows signs of an inflammatory reaction. Different types of inflammation exist, and must be distinguished carefully according to distribution and location of leukocytes and histology of the surrounding tissue. This article reviews recent findings and discusses the complex mechanisms involved in the prostatic inflammatory response. The roles of estrogen, interleukin (IL)-6, IL-8, IL-15, and IL-17 are examined.

Identification of potential diagnostic markers of prostate cancer and prostatic intraepithelial neoplasia using cDNA microarray

The identification of novel genes or groups of genes expressed in prostate cancer may allow earlier diagnosis or more accurate staging of the disease. We describe the assembly and use of a 1877-member microarray representing cDNA clones from a range of prostate cancer stages and grades, precursor lesions and normal tissue. Using labelled cDNA from tumour samples obtained from TURP or radical prostatectomy, analysis of expression patterns identified many up-regulated transcripts. Cell lines were found to over-express fewer genes than diseased tissue samples. 17 known genes were found to over-express more than 4-fold in 4 or more cancers out of 15 cancers. Only 2 genes were over-expressed in 6 out of 15 cancers or more, whilst no genes were consistently found to be over-expressed in all cancer samples. Novel prostate cancer associations for several well characterized genes or full length cDNAs were identified, including PLRP1, JM27, human UbcM2, dynein light intermediate chain 2 and human homologue of rat sec61. Novel associations with high-grade PIN include: breast carcinoma fatty acid synthase and cDNA DKFZp434B0335. We shortlist and discuss the most significant over-expressed genes in prostate cancer and PIN, and highlight expression differences between malignant and benign samples.

Serum chromogranin A: early detection of hormonal resistance in prostate cancer patients

We monitored both chromogranin A (CgA) and neuron specific enolase (NSE) in serial serum specimens from 14 patients with prostate cancer (CAP patients) showing resistance to hormonal treatment. Elevated serum CgA was detected in 10 out of these 14 patients (71%) during treatment, and an early appearance of elevated serum CgA was found in 6 of 14 (43%) of these patients when serum tPSA levels were still in the normal range. If patients with radical prostatectomy were not included, the percentage of patients showing an early appearance of elevated serum CgA would have been much higher. Elevated serum CgA levels also were found in patients not subject to hormonal therapy. Serial specimens from two out of three prostate cancer patients, randomly selected, contained elevated serum CgA. Serum NSE was not detectable in any of the serial specimens we studied, suggesting that CgA, not NSE, should be used as a marker for neuroendocrine differentiation. We also compared the serum CgA in random serum specimens between patients with BPH (benign prostate hyperplasia) and with prostate cancer in the concentration range of serum tPSA between 3-15 ng/mL. Although serum CgA concentrations in BPH patients overlapped considerably with those levels in patients with prostate cancer, levels > 100 ng/mL should suggest prostate cancer. The early appearance of elevated serum CgA allows an early change of therapy to be made and can lead to the effective prevention of any further development of metastases.

Monitoring percent free PSA in serial specimens: improvement of test specificity, early detection, and identification of occult tumors

We have measured the serum concentration of prostate specific antigen (tPSA) and determined the percent free PSA (% fPSA) in serial specimens from 64 patients with prostate cancer, 35 patients with benign prostate hyperplasia (BPH), and 3 patients with prostitis. We found that the % fPSAs were not a constant for individual patients during the course of the disease. When we compared only the % fPSA of the first specimen of serial specimens from individual patients, who were largely untreated, 37% of BPH specimens were above 22%, whereas only 1.6% cancer samples were above that value. We also found that 67% of cancer specimens and 14% of BPH samples were below 8%, respectively. Although % fPSA distribution pattern remained similar between two types of specimens, less differentiation was found between BPH and prostate cancer in random specimens compared to the study using first specimens of an individual patient's serial samples. Percent fPSA apparently are affected by treatment. However, the most important benefit for the determination of % fPSA appears to be the sensitivity of % fPSA to identify occult tumors when the tPSAs were in the normal concentration range. Determination of % fPSA also seems to improve the specificity of tPSA, not only during screening for the differentiation between BPH and prostate cancer, but also during monitoring of treatment and recurrence.