Comparison of gene expression profiles between Peyronie's disease and Dupuytren's contracture

Medical Treatment for Peyronie's Disease: Systematic Review and Network Bayesian Meta-Analysis

PURPOSE

To investigate the efficacy of medical treatment options for Peyronie's disease (PD) including oral drugs, intralesional treatment and mechanical treatment compared with placebo treatment using network meta-analysis (NMA).

MATERIALS AND METHODS

We searched the randomized controlled trials (RCTs) of PD in PubMed, Cochrane library, and EMBASE up to October 2022. RCTs included medical treatment options: oral drugs, intralesional treatment and mechanical treatment. Studies reporting at least one of the outcome measures of interest including curvature degree, plaque size, and structured questionnaires (International Index of Erectile Function, IIEF) were included.

RESULTS

Finally, 24 studies including 1,643 participants met our selection criteria for NMA. There was no statistically significant treatment compared to placebo of the curvature degree, plaque size, IIEF in Bayesian analysis. The SUCRA values of ranking probabilities for each treatment performance, which indicated that hyperthermia device ranked first in NMA. However, in frequentist analysis, 7 of mono treatments (coenzyme Q10 [CoQ10] 300 mg, hyperthermia device, interferon alpha 2b, pentoxifylline 400 mg, propionyl-L-carnitine 1 g, penile traction therapy [PTT], vitamin E 300 mg) and 2 of combination treatments ("PTT-extracorporeal shockwave treatment", "vitamin E 300 mg-propionyl-L-carnitine 1 g") were statistically significant for improvement of curvature degree, and 9 of mono treatments (CoQ10 300 mg, hyaluronic acid 16 mg, hyperthermia device, interferon alpha 2b, pentoxifylline 400 mg, propionyl-L-carnitine 1 g, verapamil 10 mg, vitamin E 300 mg, vitamin E 400 U) and 3 of combination treatments ("interferon alpha 2b-vitamin E 400 U", "verapamil 10 mg-antioxidants", "vitamin E 300 mg-propionyl-L-carnitine 1 g") were statistically significant in the improvement of plaque size.

CONCLUSIONS

At present, there is no clinical treatment alternatives that have been demonstrated to be effective compared to placebo. Nonetheless, as the frequentist approach has shown that a number of agents are efficacious, further research is expected to develop more effective treatment options.

Molecular Mechanisms and Risk Factors Related to the Pathogenesis of Peyronie's Disease

Peyronie's disease (PD) is a benign condition caused by plaque formation on the tunica albuginea of the penis. It is associated with penile pain, curvature, and shortening, and contributes to erectile dysfunction, which worsens patient quality of life. In recent years, research into understanding of the detailed mechanisms and risk factors involved in the development of PD has been increasing. In this review, the pathological mechanisms and several closely related signaling pathways, including TGF-β, WNT/β-catenin, Hedgehog, YAP/TAZ, MAPK, ROCK, and PI3K/AKT, are described. Findings regarding cross-talk among these pathways are then discussed to elucidate the complicated cascade behind tunica albuginea fibrosis. Finally, various risk factors including the genes involved in the development of PD are presented and their association with the disease summarized. The purpose of this review is to provide a better understanding regarding the involvement of risk factors in the molecular mechanisms associated with PD pathogenesis, as well as to provide insight into disease prevention and novel therapeutic interventions.

Dupuytren's disease: a localised and accessible human fibrotic disorder

We review the biology of Dupuytren's disease (DD), a common localised fibrotic disorder of the hand. The disease develops through a complex interplay of genetic and environmental factors, and epigenetic signalling. The early-stage disease nodules comprise a complex milieu of stromal and immune cells which interact to promote disease development. Recently, inhibition of tumour necrosis factor (TNF) locally resulted in softening and a decrease in nodule size, potentially controlling disease progression. Unlike fibrotic disorders of the visceral organs, the easy access to tissue in DD patients enables dissection of the cellular landscape and molecular signalling pathways. In addition, the study of DD may have wider benefits in enhancing our understanding of less-accessible fibrotic tissues.

Significant familial clustering of Peyronie's disease in close and distant relatives

BACKGROUND

Peyronie's disease (PD) has previously been observed to co-aggregate in a small number of first-degree relative pairs (e.g., father-son). However, the familial aggregation of PD in more distant relatives, as well as the aggregation of Dupuytren's disease (DD) in probands and relatives, has not been thoroughly investigated.

OBJECTIVE

This study explored the evidence for familial clustering of PD and DD in close and distant relatives.

MATERIALS AND METHODS

The Utah Population Database, which includes genealogy information linked to electronic medical records (available since 1995), was used to identify men and their relatives with PD and DD based on ICD9/10 codes. All cases were required to have high-quality genealogy data. We estimated relative risk (RR) of PD and DD in first- through fifth-degree relatives compared to matched population rates of disease. We also investigated the average relatedness of cases compared to the average relatedness of sets of matched controls. Outcome measures include estimation of relative risk and excessive relatedness as measured by a Genealogical Index of Familiality (GIF) analysis.

RESULTS

We analyzed 307 individuals with PD, and their first- through fifth-degree relatives. Approximately 0.12% of the population had PD, 95% of these were diagnosed over the age of 30 years (age range: 10-92 years), and 1.3% of PD probands had a comorbid diagnosis of DD. RR estimates for PD were significant for first- and fifth-degree relatives. RR estimates for DD were significant only for probands. The average relatedness of cases was significantly greater than matched controls, even after removing first- and second-degree relatives. We also found that 74.9% of identified PD probands belonged to pedigrees with a statistical excess of PD.

CONCLUSION

Despite the low prevalence of PD in our healthcare records, the results provide evidence that support a genetic contribution to at least a subset of PD cases.

Global Perspective on the Management of Peyronie's Disease

Introduction

Peyronie's disease is the disease that results in an alteration in the curvature of the penis, which can lead to a shortening of length, pain in erection, or difficulties in penetration, thus leading the patient to psychological alterations due to loss of functionality such as aesthetic alteration. That is why there are several studies to define the best form of treatment, which currently continues to be the first choice surgical treatment.

Objective

We present the most recommended therapies for Peyronie's disease and suggest an algorithm as a guide to direct therapy.

Methods

We used the PubMed platform to review the literature related to Peyronie's disease. Various editorials were reviewed as well as original articles and reviews focusing on the various treatments as well as their indications and results.

Results

Peyronie's disease in which conservative or drug treatment does not have a response, surgical treatment with corporoplasty, penile prosthesis implantation or both may be indicated. Corporoplasty refers to both the plication of the tunica albuginea as well as the incision of the tunica with the placement of a graft. An accurate history should always be carried out to identify erectile dysfunction as well as to be able to guide you on the repercussions of the treatment. If refractory erectile dysfunction is present, placement of a penile prosthesis with or without further adjunctive straightening maneuvers is recommended. We reviewed the indications, advantages, disadvantages, and results of the available techniques, and proposed a surgical treatment algorithm.

Conclusion

Penile shortening procedures are usually indicated in curvatures <60°, in penises with adequate length. Partial excision/incision and grafting are indicated for curvatures >60°, hourglass or hinge deformities, and short penises, if the patient's erectile function is adequate. The presence of “borderline” erectile function and/or ventral curvature tilts the choice toward shortening procedures, and refractory erectile dysfunction is an indication for penile prosthesis placement. An accurate risk/benefit assessment of the individual patient as well as meticulous patient counseling are critically important.

The contribution of the immune system to genitourinary fibrosis

Fibrotic diseases of the genitourinary tract are devastating and incompletely understood pathologies. These diseases include urethral and ureteral strictures, retroperitoneal fibrosis, and Peyronie's disease. They can contribute to obstructive uropathy and sexual dysfunction. Poor understanding of the pathophysiology of these diseases severely limits our ability to prevent and treat them. Genitourinary fibrotic diseases likely represent related pathologies that share common underlying mechanisms involving wound healing in response to injury. These diseases share the common feature of extracellular matrix abnormalities-such as collagen deposition, transforming growth factor-β accumulation, and dysregulation of collagen maturation-leading to abnormal tissue stiffness. Given the association of many of these diseases with autoimmunity, a systemic pro-inflammatory state likely contributes to their associated fibrogenesis. Herein, we explore the immunologic contribution to fibrogenesis in several fibrotic diseases of the genitourinary system. Better understanding how the immune system contributes to fibrosis in these diseases may improve prevention and therapeutic strategies and elucidate the functions of immunologic contributors to fibrosis in general.

Mineralized Peyronie's plaque has a phenotypic resemblance to bone

Mineralized Peyronie's plaque (MPP) impairs penile function. The association, colocalization, and dynamic interplay between organic and inorganic constituents can provide insights into biomineralization of Peyronie's plaque. Human MPPs (n = 11) were surgically excised, and the organic and inorganic constituents were spatially mapped using multiple high-resolution imaging techniques. Multiscale image analyses resulted in spatial colocalization of elements within a highly porous material with heterogenous composition, lamellae, and osteocytic lacuna-like features with a morphological resemblance to bone. The lower (520 ± 179 mg/cc) and higher (1024 ± 155 mg/cc) mineral density regions were associated with higher (11%) and lower (7%) porosities in MPP. Energy dispersive X-ray and micro-X-ray fluorescent spectroscopic maps in the higher mineral density regions of MPP revealed higher counts of calcium (Ca) and phosphorus (P), and a Ca/P ratio of 1.48 ± 0.06 similar to bone. More importantly, higher counts of zinc (Zn) were localized at the interface between softer (more organic to inorganic ratio) and harder (less organic to inorganic ratio) tissue regions of MPP and adjacent softer matrix, indicating the involvement of Zn-related proteins and/or pathways in the formation of MPP. In particular, dentin matrix protein-1 (DMP-1) was colocalized in a matrix rich in proteoglycans and collagen that contained osteocytic lacuna-like features. This combined materials science and biochemical with correlative microspectroscopic approach provided insights into the plausible cellular and biochemical pathways that incite mineralization of an existing fibrous Peyronie's plaque. STATEMENT OF SIGNIFICANCE: Aberrant human penile mineralization is known as mineralized Peyronie's plaque (MPP) and often results in a loss of form and function. This study focuses on investigating the spatial association of matrix proteins and elemental composition of MPP by colocalizing calcium, phosphorus, and trace metal zinc with dentin matrix protein 1 (DMP-1), acidic proteoglycans, and fibrillar collagen along with the cellular components using high resolution correlative microspectroscopy techniques. Spatial maps provided insights into cellular and biochemical pathways that incite mineralization of fibrous Peyronie's plaque in humans.

Indications and characteristics of penile traction and vacuum erection devices

A variety of devices are available for the management of patients with erectile dysfunction, Peyronie's disease, penile dysmorphophobia, for support before and after penile prosthesis insertion, and after radical prostatectomy. Traction devices include, but are not limited to, Penimaster PRO (MSP Concept, Berlin, Germany), Andropenis and Andropeyronie (Andromedical, Madrid, Spain), and the Restorex (PathRight Medical, Plymouth, USA). The other type of devices are vacuum devices such the Osbon ErecAid (Timm Medical, MN, USA). Different devices are optimal for different clinical applications, and robust and contemporary clinical data show a variety of strengths and weaknesses for each device. Research currently favours the use of traction devices for improvement of penile curvature and erectile function in patients with Peyronie's disease compared with vacuum devices; Penimaster Pro and Restorex have been shown to be associated with the best outcomes in this indication. Vacuum devices are favoured for treatment of erectile dysfunction and penile length loss after radical prostatectomy; the Osbon ErecAid is the most well-studied device for this indication. Research into other uses of vacuum and traction devices, such as for penile dysmorphophobia or before and after penile prosthesis, is very limited. Compliance, cost and availability remain substantial challenges, and further high-quality evidence is required to clarify the role of traction devices in urology and sexual medicine.

Nanostring-Based Identification of the Gene Expression Profile in Trigger Finger Samples

Trigger finger is a common yet vastly understudied fibroproliferative hand pathology, severely affecting patients' quality of life. Consistent trauma due to inadequate positioning within the afflicted finger's tendon/pulley system leads to cellular dysregulation and eventual fibrosis. While the genetic characteristics of the fibrotic tissue in the trigger finger have been studied, the pathways that govern the initiation and propagation of fibrosis are still unknown. The complete gene expression profile of the trigger finger has never been explored. Our study has used the Nanostring nCounter gene expression assay to investigate the molecular signaling involved in trigger finger pathogenesis. We collected samples from patients undergoing trigger finger (n = 4) release surgery and compared the gene expression to carpal tunnel tissue (n = 4). Nanostring nCounter analysis identified 165 genes that were differentially regulated; 145 of these genes were upregulated, whereas 20 genes were downregulated. We found that several collagen genes were significantly upregulated, and a regulatory matrix metalloproteinase (MMP), MMP-3, was downregulated. Bioinformatic analysis revealed that several known signaling pathways were dysregulated, such as the TGF-β1 and Wnt signaling pathways. We also found several novel signaling pathways (e.g., PI3K, MAPK, JAK-STAT, and Notch) differentially regulated in trigger finger. The outcome of our study helps in understanding the molecular signaling pathway involved in the pathogenesis of the trigger finger.

Molecular Mechanisms and Current Pharmacotherapy of Peyronie's Disease: A Review

Peyronie’s disease (PD) is a localized fibrotic lesion of the penis that has adverse effects on men’s health. In this review, we summarized the molecular mechanisms and pharmacotherapies of PD. A literature search was conducted using PubMed and Cochrane Library during 2001–2020. Although no oral or topical medication demonstrated efficacy in monotherapy of PD, several intralesional medications have yielded promising results. Currently, the effective strategy in management of PD should be combined modality therapy, including but not limited to pharmacotherapy, mechanical therapy, and psychotherapy. Meanwhile, basic research is still necessary to facilitate the development of novel and more reliable treatments. In future, more attention should be given simultaneously to epigenetic changes, inflammatory cytokines, the abnormal wound-healing process, and profibrotic and anti-fibrotic factors to provide more options for this refractory disease.

Fibroproliferative disorders and diabetes: Understanding the pathophysiologic relationship between Peyronie's disease, Dupuytren disease and diabetes

Introduction

Fibrosis is characterized by dysregulation and accumulation of extracellular matrix. Peyronie's disease and Dupuytren disease are fibroproliferative disorders of the tunica albuginea of the penis and fascia of the hand, respectively. Chronic hyperglycaemia due to diabetes mellitus can also lead to tissue injury and fibrosis. A meta-analysis has shown a relationship between Dupuytren disease and diabetes (overall odds ratio, 3.1; 95% confidence interval, 2.7-3.5). This review explores commonalities in the pathogenesis of Peyronie's disease, Dupuytren disease and diabetes.

Methods

A search of the PubMed database was conducted using the search terms "diabetes" AND "Peyronie's disease"; and "diabetes" AND "Dupuytren."

Results

Genome-wide association and gene expression studies conducted with tissue from people with Peyronie's disease or Dupuytren disease identified signalling pathways associated with wingless-type mammary-tumour virus integration site signalling, extracellular matrix modulation and inflammation. Biochemical studies confirmed the importance of these pathways in the pathogenesis of fibrosis with Peyronie's disease and Dupuytren disease. Dysregulation of matrix metalloproteinase activity associated with extracellular matrix breakdown was implicated in fibroproliferative complications of diabetes and in the aetiology of Peyronie's disease and Dupuytren disease. A notable percentage of people with diabetes have comorbid Peyronie's disease and/or Dupuytren disease.

Conclusions

Studies have not been performed to identify fibroproliferative pathways that all 3 conditions might have in common, but data suggest that common pathways are involved in the fibroproliferative processes of Peyronie's disease, Dupuytren disease, and diabetes.

A Population-Based Study of Peyronie's Disease in Turkey: Prevalence and Related Comorbidities

INTRODUCTION

Peyronie's disease (PD) prevalence varies between 0.39% and 20% and studies on PD prevalence are limited.

AIM

This study aims to determine the prevalence of PD in males aged ≥30 years in Turkey and to evaluate etiological factors associated with it.

METHODS

The study was conducted in 12 regions of Turkey according to the Eurostat Nomenclature of Territorial Units for Statistics 1 classification and included 1,208 patients. Survey questionnaires including questions about demographic features and basic health status as well as about diagnosis and etiology of PD were put forth to the volunteers who agreed to participate in the study. Diagnosis of probable PD was established by evaluating the questionnaires. Patients with a diagnosis of congenital penile curvature were excluded from the group with PD. Chi-square test, Fisher's exact test, and Mann-Whitney U test were used.

MAIN OUTCOME MEASURE

The primary outcome analyzed in this article was the prevalence rate of PD in Turkey and the associated comorbidities.

RESULTS

The prevalence of PD was determined as 5.3%. The rates of participants with PD were found to be the highest in the 50-59 years group (27%) and in the North-East Region (20%). Compared with participants without PD, participants with PD were older (median: 52 interquartile range [41-64] vs 45 [37-55]; P < .001) and the rates of smokers (73% vs 60.9%; P = .036) and those having diabetes mellitus (17.5% vs 9.2%; P = .045), hypertension (14.3% vs 6.9%; P = .041), and heart failure were higher (7.9% vs 2.5%; P = .027). Male with PD symptoms preferred their partners on top during sexual intercourse (15.2% vs 34.1%; P < .001). This is the first study to evaluate premature ejaculation prevalence and related comorbidities with face-to-face interviews.

CONCLUSION

The prevalence of PD was 5.3% in Turkey. Besides advanced age, smoking, position of sexual intercourse, and presence of comorbidities especially diabetes mellitus, hypertension, and heart failure were the factors associated with PD prevalence. Kadioglu A, Dincer M, Salabas E, et al. A Population-Based Study of Peyronie's Disease in Turkey: Prevalence and Related Comorbidities. Sex Med 2020;8:679-685.

The Molecular Pathogenesis of Dupuytren Disease: Review of the Literature and Suggested New Approaches to Treatment

BACKGROUND

Ever since the classification of Dupuytren disease into the proliferative, involutional, and residual stages, extensive research has been performed to uncover the molecular underpinnings of the disease and develop better treatment modalities for patients. The aim of this article is to systematically review the basic science literature pertaining to Dupuytren disease and suggest a new approach to treatment.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a systematic review was conducted using the MEDLINE database to identify basic science literature on Dupuytren pathophysiology falling under 1 or more of the following categories: (1) Molecular alterations, (2) Structural alterations, and (3) Genetic predisposition.

RESULTS

A total of 177 articles were reviewed of which 77 studies met inclusion criteria. Articles were categorized into respective sections outlined in the study methods.

CONCLUSION

The pathophysiological changes involved in Dupuytren's disease can be divided into a number of molecular and structural alterations with genetic predisposition playing a contributory role. Understanding these changes can allow for the development of biologics which may disrupt and halt the disease process.

Advances in stem cell therapy for the treatment of Peyronie's disease

Peyronie's disease (PD) is a connective tissue disorder of the penis characterized by fibrosis and plaque formation within the tunica albuginea. PD is characterized by painful penile curvature that impairs sexual intercourse. Stem cell therapy is one of the recent non-invasive treatment options for patients with PD and it has promising results. Stem cells are undifferentiated cells that are capable of self-renewal and differentiation, promoting the repair of tissues via their immunomodulatory and anti-inflammatory action. Adipose-derived stem cells (ADSC) are used most widely due to their abundant tissue source and ease of isolation. Multiple studies have indicated the efficacy of stem cell therapy as a potential treatment for fibrotic diseases. Clearly, ADSCs may represent a way to treat and prevent PD in both rat and human models. Further clinical studies are needed to confirm the efficacy of stem cell therapy for PD in humans.

Peyronie's Disease Intervention Studies: An Exploration of Modern-Era Challenges in Study Design and Evaluating Treatment Outcomes

INTRODUCTION

Peyronie's disease (PD) is characterized by pain, deformity, sexual dysfunction, and psychological bother. Several treatments are available with varying levels of efficacy, and significant limitations exist with the currently available literature.

AIM

To explore modern-era methodological challenges inherent to PD research as they pertain to intervention studies.

METHODS

We performed a critical review of the PD intervention literature to identify common methodological challenges with emphasis on aspects of patient assessment and treatment outcomes, study design, and statistical analysis. The key objective was to provide an impetus on which to build future research protocols, rather than focus on weaknesses with any individual studies.

MAIN OUTCOME MEASURE

Expert opinion was used to summarize limitations with commonly reported objective outcomes such as penile curvature, girth, and length along with imaging modalities and objective questionnaires. Appropriate study design and statistical analysis were also reviewed to discuss common pitfalls in the PD literature.

RESULTS

There are multiple shortcomings inherent to studying objective PD outcomes such as penile curvature, girth, and length. These include lack of standardized protocols for preintervention and postintervention assessment, interobserver and intraobserver variability, and lack of consistent definitions for what defines an objective outcome as clinically "meaningful" for patients. Similarly, imaging studies including penile ultrasound are subject to marked variation, thereby limiting their utility to measure predefined primary or secondary study outcomes including cavernosal artery hemodynamics and penile plaque size. Objective and validated questionnaires such as the Peyronie's Disease Questionnaire and International Index of Erectile Function require that patients have recently engaged in sexual activity, which is challenging for many patients as a result of penile deformity with PD. Finally, careful study design and statistical analysis (including appropriate study power) are imperative to ensure reliable results. Current shortcomings in the majority of studies contribute to the low level of evidence available for most PD interventions.

CLINICAL IMPLICATIONS

Future PD intervention studies should focus on optimizing study design and statistical analysis. Furthermore, authors must incorporate standardized protocols for assessing preintervention and postintervention outcomes.

STRENGTH & LIMITATIONS

The current analysis and recommendations for future study are based on the expertise and opinion of the manuscript authors.

CONCLUSION

Multiple areas of weakness in study design, statistical analysis, and patient outcomes assessment limit the reliability of data derived from PD intervention studies in the modern era. The global themes identified herein should serve as a basis upon which to build future research protocols. Ziegelmann MJ, Trost LW, Russo GI, et al. Peyronie's Disease Intervention Studies: An Exploration of Modern-Era Challenges in Study Design and Evaluating Treatment Outcomes. J Sex Med 2020;17:364-377.

Increased Risk of Incident Disease in Men with Peyronie's Disease: Analysis of U.S. Claims Data

BACKGROUND

The subsequent health risks associated with Peyronie's disease (PD) are unknown.

AIM

This cohort study assesses the risk of developing auto-immune conditions and common chronic health conditions after a diagnosis of PD. We hypothesize that an increase in auto-immune disease will be evident in men with PD, as has been suggested in smaller studies.

METHODS

We determined the longitudinal incidence of 13 auto-immune diseases and 25 common chronic conditions in a cohort from the Truven Health Analytics (Ann Arbor, Michigan, USA) database from 2007-2013. The cohort included men with 1 of 3 exposures in 2007: (1) men with PD, (2) men with erectile dysfunction (ED) but not PD, and (3) men without PD or ED, matched on age and follow-up duration.

OUTCOMES

To assess incidence, we utilized a Cox regression model adjusting for age, smoking, obesity, health care visits per year, urology visits per year, and years of follow-up.

RESULTS

We included 8,728 men with PD; 204,147 men with ED; and 87,280 controls. Men with PD had an increased risk of developing benign prostatic hyperplasia (hazard ratio [HR] 1.21, 95% CI 1.16-1.27), prostatitis (HR 1.21, 95% CI 1.12-1.31), and lower urinary tract symptoms (HR 1.10, 95% CI 1.05-1.16) when compared to both men with ED and age-matched controls without ED or PD even when controlling for the number of urology visits per year. Compared to controls, men with PD also had an increased risk of developing keloids. No significant risk for any auto-immune disease was observed.

CLINICAL IMPLICATIONS

Clinicians should have heightened awareness for these relevant co-morbidities when treating men with PD.

STRENGTHS & LIMITATIONS

Utilizing a claims database provides one of the largest cohorts of men with PD ever published but claims databases lack some individual patient data such as risk factors and demographic information relevant to PD, including: penile injury, history of urologic procedures, and other lifestyle factors.

CONCLUSION

Men with PD had a higher risk of benign prostatic hyperplasia, lower urinary tract symptoms, prostatitis, and keloids after a diagnosis of PD, but no increased risk of auto-immune conditions. These findings suggest a common etiology for these conditions that may manifest itself in diseases at different times in men's life cycle. Pastuszak AW, Rodriguez KM, Solomon ZJ, et al. Increased Risk of Incident Disease in Men with Peyronie's Disease: Analysis of U.S. Claims Data. J Sex Med 2018;15:894-901.

The Etiology of Peyronie's Disease: Pathogenesis and Genetic Contributions

INTRODUCTION

Peyronie's disease (PD) is a chronic fibrosing condition that contributes to penile deformity, curvature, and pain. Initial familial studies demonstrated potential genetic links to PD. Since that time, very few investigations have significantly advanced the science in this area. Hence, there is a large opportunity and significant need to better study the underlying genomics and pathogenesis of PD.

AIM

To summarize the current genomic literature relevant to PD.

METHODS

A review was performed of all PubMed-indexed literature from 1970-2018 relating to the pathophysiology and genetics of PD. Key findings were categorically summarized to include epidemiology, risk factors, inheritance patterns, chromosomal instability, genetic associations, epigenetics, differential gene expression, and preclinical models of PD.

MAIN OUTCOME MEASURES

Summary of the current literature on the genetics of PD.

RESULTS

PD is a common condition and has several known risk factors and comorbid disease associations. Although men with PD are believed to be genetically predisposed, there are likely several subtypes of the condition, each with varied pathophysiological disorders and contributing factors. Available data suggest that PD is associated with underlying genetic instability, including dysregulation of genes relating to fibrosis and cellular degradation, thus, resulting in abnormal plaque development and penile deformity. Preclinical models, including cell cultures and rat models, demonstrate several consistencies with PD clinical and histopathologic characteristics; however, an ideal model with spontaneous development of PD is lacking.

CONCLUSION

Based on limited data, PD likely represents a heterogeneous condition, with both heritable and environmentally-driven epigenetic factors contributing to its development and progression. However, there remains a significant gap in the literature on the underlying cause and pathophysiology of the condition, suggesting a substantial need for further investigation and study. Sharma KL, Alom M, Trost L. The Etiology of Peyronie's Disease: Pathogenesis and Genetic Contributions. Sex Med Rev 2020;8:314-323.

Evaluation of Oral Pentoxifylline, Colchicine, and Penile Traction for the Management of Peyronie's Disease

Introduction

Currently, there are several treatment options for Peyronie disease (PD). Although surgical interventions have better reported outcomes than conservative therapy, surgery is not suitable for all patients with PD. Therefore, oral therapy for PD is still a frequently used treatment due to low cost, convenience and limited side effects. However, current literature on the efficacy of oral therapy in PD is inconclusive. Pentoxifylline and colchicine have both shown some promise though further studies are required to confirm their effectiveness.

Aim

The aim of this study was to assess the efficacy of oral therapy for PD, including pentoxifylline and colchicine, coupled with the Andropenis penile traction therapy (PTT) extender on degree of penile curvature and plaque size.

Methods

Between March 2015 and June 2018, a prospectively collected database for patients receiving oral therapy for PD (pentoxifylline and/or colchicine) was reviewed.

Main Outcome Measure

Collected data variables were compared at baseline and after 6 months of treatment, including degree of curvature, plaque size, and penile Doppler ultrasound parameters (peak systolic velocity, minimum diastolic velocity, and pulsatility index). PTT was applied by the patient for a total of 1 hour per day for 6 months.

Results

A total of 46 patients were involved in this study. Mean age was 56 ± 10 years. There was a significant decrease in the degree of penile curvature after 6 months (55.8º ± 20º vs 41.4º ± 20.8º; P = .03). Likewise, the plaque size decreased significantly from 5.42 ± 2.7 to 2.42 ± 1.71 cm²; P = .0001. There was a significant increase in the peak systolic velocity from 29.8 ± 10.02 to 38.2 ± 11cm/sec; P = .02, whereas no statistically significant difference could be detected regarding end diastolic velocity (M = 0.56 ± 3.1 vs 1.59; P = .415) or pulsatility index (M_diff = 0.03; CI = -0.06 to 0.12; P = .473). Furthermore, there was no statistically significant difference in medication type of pentoxifylline or colchicine (M_diff = 17.23; CI = -3.31 to 37.77; P = .09).

Conclusion

Altogether, pentoxifylline and colchicine, taken with concomitant PTT, present a potentially convenient, low cost, and effective treatment for penile curvature and plaque resulting from PD. Prospective randomized trials are still required for better evaluation of the course of PD with patients undergoing conservative management.

Ibrahim A, Gazzard L, Alharbi M, et al. Evaluation of Oral Pentoxifylline, Colchicine, and Penile Traction for the Management of Peyronie’s Disease. Sex Med 2019;7:459–463.

A review of inflammation and fibrosis: implications for the pathogenesis of Peyronie's disease

Peyronie's disease (PD) is a superficial fibrosing disorder that causes penile deformity and can interfere with sexual intercourse and reproduction, as well as diminish quality of life. While the exact mechanism of PD is still being investigated, there is likely a genetic component to the predisposition to penile plaque formation. Ultimately, however, perturbations in normal wound healing and aberrant deposition of extracellular matrix components lead to fibrotic tissue deposition. Fibrosis in PD is regulated by a complex pathway of inflammatory and fibrotic mediators. Currently there are no treatments for PD that address an underlying cause or disease progression. In this review, we provide an overview of the known inflammatory and fibrotic mediators of PD and explore the pathophysiology of other human superficial fibrosing disorders to develop further insights into PD.

Optimizing collagenase Clostridium histolyticum therapy for Peyronie's disease using a novel approach with percutaneous needle tunnelling

OBJECTIVES

To compare the efficacy and safety of a combined treatment of percutaneous needle tunnelling (PNT) and a modified collagenase Clostridium histolyticum (CCH) protocol (PNT/CCH) vs the modified protocol alone (CCH) in the treatment of Peyronie's disease (PD).

PATIENTS AND METHODS

A prospective registry of patients treated with a modified CCH protocol was maintained between June 2014 and February 2018. The last 50 patients received PNT as an adjuvant therapy (PNT/CCH), and their data were compared with those of the other 94 patients treated previously (CCH). PNT involves the creation of multiple holes made percutaneously in the plaque before each injection. The modified protocol consisted of two collagenase injections, at 1-week intervals, followed by penile modelling. Patients used penile traction therapy, tadalafil and pentoxifylline for the next 2 months and were followed up for 6 months. The main outcome was improvement of curvature. Secondary outcomes were improvements in erectile function, PD symptoms, stretched penile length and satisfaction.

RESULTS

Improvement in curvature was greater in patients in the PNT/CCH group than in the CCH group (mean ± sd 19.2 ± 6.1° vs 12.7 ± 5.0°; P < 0.001 [36.2 ± 12.5% vs 28.1 ± 14.5%; P = 0.001]). Compared with baseline, both interventions were associated with significant improvement in secondary outcomes. The main complications were ecchymosis, bruising and penile pain, with no significant differences between groups.

CONCLUSIONS

Treatment of PD with CCH using our modified protocol in combination with PNT is safe and more effective than the modified protocol alone, with the potential for improved cost-effectiveness.

Devices for penile traction: the long and winding road to treating Peyronie's disease

INTRODUCTION

Penile traction therapy (PTT) is increasingly being recognized as a viable nonsurgical approach to Peyronie's disease (PD). The goal of this article is to review the current literature on PTT with attention to traction protocols, devices, and outcomes.

AREAS COVERED

Literature on the pathophysiology of PD, PTT as primary and adjunctive treatment for PD, perioperative use of PTT, and vacuum erection devices are all reviewed. Pertinent literature was obtained from the PubMed database. The key words 'penile traction,' 'mechanotransduction,' and 'Peyronie's disease' were searched and results were narrowed down based on relevance to the review.

EXPERT COMMENTARY

PTT appears beneficial but the true magnitude of effect is difficult to discern. Most studies are not randomized, have small sample sizes, lack control arms, or have varying traction protocols. Patient compliance is critical and new devices and traction protocols are needed to maximize the benefit of PTT.

Extracellular matrix alterations after blood instillation in tunica albuginea of rats

The cause of Peyronie's disease (PD) is still not completely understood. The objective of this study, therefore, was to analyze the histological and biochemical alterations that occur after the instillation of blood in the tunica albuginea (TA) of rats with an emphasis on the remodeling process of ECM. Thirty male Wistar rats were divided into 4 groups: two control groups with instillation of distilled water in TA followed by penectomy after 15 days or 45 days, respectively and two experimental groups with instillation of blood in TA followed by penectomy after 15 days or 45 days, respectively. Histological, immunofluorescent and immunohistochemical analyses were performed. The higher presence of fibrotic tissue in rats injected with blood demonstrated alterations in TA similar to inflammation found in PD. The increased expression of TGF-β, MMP9, HPSE, and biglycan associated with the decreased expression of syndecan-1 and aggrecan in the experimental groups suggested an enhancement in the remodeling of ECM. The results contribute to show that blood instillation on TA appears to trigger alterations in the ECM similar to the ones found in inflammatory diseases such as PD.

The Hand of Sabazios: Evidence of Dupuytren’s Disease in Antiquity and the Origin of the Hand of Benediction

Dupuytren’s disease gained its eponym from the surgeon Baron Guillaume Dupuytren (1777-1835). However, the terms “Cline’s contracture” and “Cooper’s contracture,” named after the two surgeons who proposed the treatment for the palmar contractures prior to Dupuytren, have also been used to describe the disease. In addition to the eponyms attributed to these three surgeons, a number of other appellations with interesting provenance exist for Dupuytren’s disease including the “Curse of the MacCrimmons,” “Celtic hand,” “Viking’s disease,” and the “Hand of Benediction.” These terms all have interesting provenance; however, contention exists with regard to the appropriateness of their coinage. Of these terms, the “Hand of Benediction” is based upon the oldest history, supposedly thought to be a result of an early Pope afflicted with Dupuytren’s disease. This report suggests that Dupuytren’s disease was recorded in history prior Christianity, the Vikings, as well as Dupuytren, Cline, and Cooper. Nearly 100 votive “Hand of Sabazios” artifacts from Antiquity appear to document Dupuytren’s disease via sculpture. The report posits that Dupuytren’s disease may have been represented by the “Hand of Sabazios,” subsequently inspiring the “Hand of Benediction” and “Hand of God” that has permeated Christian art and culture for thousands of years.

Prevalence of Peyronie's Disease-Like Symptoms in Men Presenting With Dupuytren Contractures

Introduction

Peyronie's disease (PD) and Dupuytren contractures (DC) are often comorbid and are believed to have a similar underlying pathophysiologic mechanism.

Aim

To investigate the prevalence of PD-like symptoms (PDLS) in men with DC.

Methods

From October 2013 to December 2016, men who were seen and evaluated for DC were offered the opportunity to participate in an anonymous survey. The survey assessed several basic demographic and sexual health factors and included items from the International Index of Erectile Function and the Erection Hardness Scale. Men who reported PDLS were asked a series of questions derived from the Peyronie's Disease Questionnaire and for their opinions on theoretical treatment modalities for sexual problems and penile deformity.

Main Outcome Measure

Prevalence of PDLS in men with DC.

Results

One hundred forty men with DC were invited to participate; 85 surveys were returned (response rate = 61%). Twenty-two respondents (26%, 95% confidence interval = 17–35) reported PDLS. Approximately one fourth of all respondents had an Erection Hardness Scale score lower than 3. The most common specific PDLS concerns were penile curvature (91%), length loss (55%), narrowing (36%), and hinging (32%). In men with PDLS, 73% felt at least a little bothered by the symptoms when attempting sexual activity and 40% reported having sex less frequently because of the symptoms. Just 27% of men with PDLS had ever used a treatment for a sexual concern. In terms of treatments for penile deformities, 64% of men with PDLS expressed an interest in treatment administered in the form of an in-office procedure; 41% were potentially amenable to a surgical procedure.

Conclusion

The prevalence of PDLS in men with DC is similar to the prevalence of DC in men diagnosed with PD. A substantial number of these men have distress and would consider standard-of-care treatments for PD.

Shindel AW, Sweet G, Thieu W, et al. Prevalence of Peyronie's Disease-Like Symptoms in Men Presenting With Dupuytren Contractures. Sex Med 2017;5:e135–e141.

Connective Tissue Degeneration: Mechanisms of Palmar Fascia Degeneration (Dupuytren's Disease)

Dupuytren's disease is a connective tissue disorder of the hand causing excessive palmar fascial fibrosis with associated finger contracture and disability. The aetiology of the disease is heterogeneous, with both genetic and environmental components. The connective tissue is abnormally infiltrated by myofibroblasts that deposit collagen and other extracellular matrix proteins. We describe the clinical profile of Dupuytren's disease along with current therapeutic schemes. Recent findings on molecular and cellular parameters that are dysregulated in Dupuytren's disease, which may contribute to the onset of the disease, and the role of resident inflammation promoting fibrosis, are highlighted. We review recent literature focusing on non-myofibroblast cell types (stem cell-like cells), their pro-inflammatory and pro-fibrotic role that may account for abnormal wound healing response.

Penile traction therapy for Peyronie's disease-what's the evidence?

Penile traction therapy (PTT) is a new therapeutic option for men with Peyronie’s disease (PD). However, it has a long history of use in other fields of medicine including bone, skin, skeletal muscle, and Dupuytren’s. Mechanotransduction, or gradual expansion of tissue by traction, leads to the formation of new collagen tissue by cellular proliferation. As a molecular result, continuous extension of the fibrous plaque causes significant increases in collagenase and metalloproteinases, and, ultimately, to fibrous plaque softening and extension. This hypothetical knowledge has been supported by recent well designed experimental studies. Furthermore, several clinical papers have provided promising results on the use of PTT in PD patients. It has been shown in some series that the use of PTT significantly increases flaccid and stretched penile lengths and results in significant penile curvature improvement when compared to baseline. Furthermore, the use of PTT concomitantly with either verapamil or interferon α-2b has also been shown to be an effective therapy. Additionally, the beneficial effect of PTT on penile length before or after penile surgery in men with corporal fibrosis has been described. Finally, as a minimally invasive alternative treatment option to penile augmentation surgery in men with dysmorphophobia, PTT use has shown promising results by several experts. Studies have shown that PTT provides an acceptable, minimally invasive method that can produce effective and durable lengthening of the penis in men complaining of a small/short penis. There are, however, several criticisms related to the designs of the reported studies, such as small sample size and selection bias. Well-designed studies with larger numbers of patients and longer follow-up periods are, however, needed to establish the true benefits of PTT.

Update on the role of molecular factors and fibroblasts in the pathogenesis of Dupuytren's disease

The mechanism by which the fibroblast is able to trigger palmar fibromatosis is still not yet fully understood. It would appear certain that the "abnormal" fibroblasts continuously synthesise profibrotic cytokines which are able to determine the activation to myofibroblasts, to stimulate them to the further proliferation and synthesis of other cytokines, to modify the cells' differentiation and ultrastructural characteristics, as well as the production of matrix and other proteins. Several fibroblast growth factors have been suggested to be responsible of an abnormal cell activation with an aberrantly elevated collagen synthesis and extracellular deposition in Dupuytren's disease, as TGF-Beta, TNF-Alfa, PDGF, GM-CSF, free radicals, metalloproteinases, sex hormones, gene modified expression, mechanical stimulation. The Authors review the current state of knowledge in the field, by analyzing the role of these cytokines in the palmar fibromatosis.

Peyronie's disease: a literature review on epidemiology, genetics, pathophysiology, diagnosis and work-up

Peyronie's disease (PD), a fibromatous disorder of the tunica albuginea of the penile corpus cavernosum, named after the French physician Francois de la Peyronie, is characterized by pain, plaque formation, penile curvature, and plaque calcification. The epidemiological data on PD is inconsistent, with recent reports stating a prevalence of up to 9%, and the condition affecting men of all ages, from teenagers to septuagenarians. We are just beginning to elucidate the role of genetics as a causative factor for PD. Chromosomal abnormalities and single-nucleotide polymorphisms have been shown to be associated with fibrotic diatheses. Tunical mechanical stress and microvascular trauma are major contributory factors to the pathophysiology of PD. The diagnosis of PD can be made using a combination of clinical history, physical examination and, sometimes, imaging modalities. A better understanding of the molecular pathophysiology of this condition remains paramount for the development of newer and more effective disease-targeted interventions.

The Genetic Basis of Peyronie Disease: A Review

INTRODUCTION

Peyronie disease (PD) is a progressive fibrotic disorder of the penile tunica albuginea that results in fibrotic penile plaques and can lead to penile deformity. Characterized by aberrant fibrosis resulting in part from the persistence of myofibroblasts and altered gene expression, the molecular factors underpinning PD and other related fibrotic diatheses are just being elucidated. A genetic link to PD was first identified three decades ago using pedigree analyses. However, the specific genetic factors that predispose patients to aberrant fibrosis remain unknown, and the relations between these fibrotic conditions and other heritable diseases, including malignancy, are uncharacterized.

AIM

To review the current landscape linking molecular and genetic factors to aberrant fibrosis in PD and related fibrotic diatheses, including Dupuytren disease.

METHODS

Review and evaluation of the literature from 1970 to the present for genetic factors associated with PD were performed.

MAIN OUTCOME MEASURES

Data describing the genetic factors associated with PD were obtained.

RESULTS

We describe the known structural chromosomal abnormalities and single-nucleotide polymorphisms associated with fibrotic diatheses and discuss the spectrum of differential gene expression data comparing normal tissues with those derived from men with PD or Dupuytren disease. We discuss epigenetic mechanisms that might regulate gene expression and alter predisposition to fibrosis.

CONCLUSION

Although the current understanding of the genetic factors associated with PD is limited, significant advances have been made during the past three decades. Further research is necessary to provide a more comprehensive understanding of the landscape of genetic factors responsible for the development of PD.

Dupuytren's disease therapy: targeting the vicious cycle of myofibroblasts?

INTRODUCTION

Dupuytren's disease (DD) is a proliferative fibromatosis of the hand, which causes permanent flexion contracture of the digits and, ultimately, loss of function. The treatment of DD is complex and involves surgical and nonsurgical approaches, with the goal of removing the affected tissue. New biological targets are under investigation in order to develop innovative therapies.

AREAS COVERED

The etiology of DD is still unknown. Several authors who focused their studies on the genetics of DD recognized an inherited autosomal dominant pattern. Actually, DD is a multifactorial and complex disease. Myofibroblasts are thought to play a crucial role in its pathogenesis, although their origin is not clear.

EXPERT OPINION

There is a general consensus that a better understanding of cellular and molecular mechanisms of DD will lead to the design of more specific and effective treatment alternatives. In this review, the authors hypothesize a new biological model for DD pathology, where myofibroblasts enhance the reservoir of the disease acting as if in a vicious cycle. This could help, ultimately, in identifying new therapeutic strategies to treat this common and disabling fibroproliferative disorder.

Tunica albuginea allograft: a new model of LaPeyronie's disease with penile curvature and subtunical ossification

The pathophysiology of LaPeyronie's disease (PD) is considered to be multifactorial, involving genetic predisposition, trauma, inflammation and altered wound healing. However, these factors have not yet been validated using animal models. In this study, we have presented a new model obtained by tunica albuginea allograft. A total of 40, 16-week-old male rats were used. Of these, 8 rats served as controls and underwent a 10 × 2-mm-wide tunical excision with subsequent autografting, whereas the remaining 32 underwent the same excision with grafting of the defect with another rat's tunica. Morphological and functional testing was performed at 1, 3, 7 and 12 weeks after grafting. Intracavernous pressure, the degree of penile curvature and elastic fiber length were evaluated for comparison between the allograft and control groups. The tissues were obtained for histological examination. The penile curvature was significantly greater in the allografted rats as compared with the control rats. The erectile function was maintained in all rats, except in those assessed at 12 weeks. The elastin fiber length was decreased in the allografted tunica as compared to control. SMAD2 expression was detected in the inner part of the allograft, and both collagen-II- and osteocalcin-positive cells were also noted. Tunica albuginea (TA) allograft in rats is an excellent model of PD. The persistence of curvature beyond 12 weeks and the presence of ossification in the inner layer of the TA were similar to those observed in men with PD. Validation studies using this animal model would aid understanding of the PD pathophysiology for effective therapeutic interventions.

Therapeutic advances in the treatment of Peyronie's disease

Peyronie's disease (PD) is an under-diagnosed condition with prevalence in the male population as high as 9%. It is a localized connective tissue disorder of the penis characterized by scarring of the tunica albuginea. Its pathophysiology, however, remains incompletely elucidated. For the management of the acute phase of PD, there are currently numerous available oral drugs, but the scientific evidence for their use is weak. In terms of intralesional injections, collagenase clostridium histolyticum is currently the only Food and Drug Administration-approved drug for the management of patients with PD and a palpable plaque with dorsal or dorsolateral curvature >30°. Other available intralesional injectable drugs include verapamil and interferon-alpha-2B, however, their use is considered off-label. Iontophoresis, shockwave therapy, and radiation therapy have also been described with unconvincing results, and as such, their use is currently not recommended. Traction therapy, as part of a multimodal approach, is an underused additional tool for the prevention of PD-associated loss of penile length, but its efficacy is dependent on patient compliance. Surgical therapy remains the gold standard for patients in the chronic phase of the disease. In patients with adequate erectile function, tunical plication and/or incision/partial excision and grafting can be offered, depending on degree of curvature and/or presence of destabilizing deformity. In patients with erectile dysfunction non-responsive to oral therapy, insertion of an inflatable penile prosthesis with or without straightening procedures should be offered.

PEYRONIE'S DISEASE: A REVIEW OF ETIOLOGY, DIAGNOSIS, AND MANAGEMENT

Peyronie's Disease (PD) is a superficial fibrosing disorder of the penis resulting in plaque formation and penile deformity. Once considered rare, PD has more recently been found in up to 13% of men, and can negatively affect sexual and psychosocial function of both patients and their partners. While the etiology of PD is unclear, it is thought to result from an inciting traumatic event followed by aberrant fibrosis or dysregulated wound healing. The evaluation of men presenting with PD includes a detailed history and physical exam, focusing on the penis in both the flaccid and erect states. PD is often associated with erectile dysfunction (ED), as well as several other comorbidities. Laboratory testing is not needed to diagnose PD, although given the associations between PD and systemic diseases including hypogonadism, diabetes, and cardiovascular disease, screening and work-up for these conditions in men with PD may be warranted. Treatment modalities for PD are diverse and include oral, topical, intralesional, mechanical, and surgical therapies. Oral, topical, and mechanical therapies generally have little evidence supporting their efficacy. Several intralesional therapies, including interferon α2b and collagenase Clostridium hystiolyticum have demonstrated efficacy in the treatment of PD. Surgical treatment, indicated in men with significant, stable deformity, includes plication of the tunica albuginea, plaque incision/excision and grafting, and placement of inflatable penile prosthesis (IPP) with or without additional maneuvers to achieve desired results, and has high success rates.

The transcriptional signatures of cells from the human Peyronie's disease plaque and the ability of these cells to generate a plaque in a rat model suggest potential therapeutic targets

INTRODUCTION

The success of medical therapies for Peyronie's disease (PD) has not been optimal, possibly because many of them went directly to clinical application without sufficient preclinical scientific research. Previous studies revealed cellular and molecular pathways involved in the formation of the PD plaque and in particular the role of the myofibroblast.

AIMS

The current work aimed to determine under normal and fibrotic conditions what differentiates PD cells from tunica albuginea (TA) and corpora cavernosa (CC) cells by defining their global transcriptional signatures and testing in vivo whether PD cells can generate a PD-like plaque.

METHODS

Human TA, PD, and CC cells were grown with transforming growth factor beta 1 (TGFβ1; TA+, PD+, CC+) or without it (TA-, PD-, CC-) and assayed by (i) immunofluorescence, Western blot and RT-PCR for myofibroblast, smooth muscle cell and stem cell markers; (ii) collagen content; and (iii) DNA microarray analysis. The ability of PD+ cells to induce a PD-like plaque in an immuno-suppressed rat model was assessed by Masson trichrome and Picrosirius Red stainings.

MAIN OUTCOMES MEASURES

Fibroproliferative features of PD cells and identification of related key genes as novel targets to reduce plaque size.

RESULTS

Upon TGFβ1stimulation, collagen levels were increased by myofibroblasts in the PD+ but not in the CC+ cells. The transcriptional signature of the PD- cells identified fibroproliferative, myogenic (myofibroblasts), inflammatory, and collagen turnover genes that differentiate them from TA- or CC- cells and respond to TGFβ1 with a PD+ fibrotic phenotype, by upregulation of IGF-1, ACTG2, MYF5, ACTC1, PSTN, COL III, MMP3, and others. The PD+ cells injected into the TA of the rat induce a PD-like plaque.

CONCLUSIONS

This suggests a novel combination therapy to eliminate a PD plaque by targeting the identified genes to (i) improve collagenase action by stimulating endogenous metalloproteinases specific to key collagen types and (ii) counteract fibromatosis by inhibiting myofibroblast generation, proliferation, and/or apoptosis.

Experience in the use of collagenase clostridium histolyticum in the management of Peyronie's disease: current data and future prospects

INTRODUCTION

Peyronie's disease (PD) is a chronic wound-healing disorder characterized by formation of fibrous inelastic scarring of the tunica albuginea resulting in a variety of penile deformities. In most cases, PD is accompanied by a physical and psychological impact. Xiaflex® is an injectable collagenase clostridium histolyticum (CCh) preparation consisting of a predetermined mixture of two distinct collagenases. Recently the US Food and Drug Administration (FDA) approved Xiaflex® for the nonsurgical treatment of men with PD with curvature of 30° or more and tangible scar tissue plaque in their penis.

METHOD

This article presents a comprehensive review of the updated information on the use of Xiaflex® for the nonsurgical treatment of PD.

RESULTS

Mean improvements in penile curvature ranging from 29% to 34% and in bother domain scores have been reported. The majority of the reported adverse effects are mild or moderate and 79% resolve without intervention.

CONCLUSION

The combined results of these trials have led to the FDA approval of CCh for the treatment of PD. However, the long-term effects and results need further investigation, with large follow-up series. Considering these results, future perspectives will probably result in the use of a combined or sequential therapy including CCh.

Peyronie's disease: epidemiology, diagnosis, and management

OBJECTIVE

Peyronie's disease (PD) is a progressive fibrotic disorder of the penis that is characterized by formation of collagen plaques on the tunica albuginea of the penis that may result in penile deformity, pain (typically early in the disease course), and often occurs in conjunction with erectile dysfunction. This review's purpose is to raise awareness of PD among primary care physicians, who are likely to provide the initial diagnosis and information to patients.

METHODS

PubMed was searched for articles related to epidemiology, diagnosis, and management of PD. Reference lists of relevant articles were also examined for further pertinent research. Following the goals of this review, references were selected based on their appropriateness for a primary care audience.

RESULTS

The symptoms of PD may physically limit intercourse and impose a severe physical and psychological burden. The course of PD includes an early 'inflammatory' phase that may last 1-18 months and a subsequent 'stable' phase. In the early phase, patients may experience penile pain as the tunical plaque develops. During the stable phase, the plaque becomes more organized, penile curvature stabilizes, and the pain usually subsides. Currently, there are no US Food and Drug Administration approved therapies that have shown significant efficacy for PD. Nonsurgical treatment options are often used to manage PD with variable success. Most studies of nonsurgical management of PD are small, poorly controlled, and include patients in variable disease stages. Surgical treatment of PD is reserved for stable patients with erectile dysfunction and penile deformity that impairs sexual function.

CONCLUSION

PD is frequently undiagnosed. Even when PD is correctly identified, choice of treatment is problematic, based on the limited currently available clinical data demonstrating clinical benefits associated with treatment. Newer medications in clinical testing seem to offer some potential benefit for men with PD, though further research is necessary.

The immunology of fibrosis

Fibrosis is the production of excessive amounts of connective tissue, i.e., scar formation, in the course of reactive and reparative processes. Fibrosis develops as a consequence of various underlying diseases and presents a major diagnostically and therapeutically unsolved problem. In this review, we postulate that fibrosis is always a sequela of inflammatory processes and that the many different causes of fibrosis all channel into the same final stereotypical pathways. During the inflammatory phase, both innate and adaptive immune mechanisms are operative. This concept is exemplified by fibrotic diseases that develop as a consequence of tissue damage, primary inflammatory diseases, fibrotic alterations induced by foreign body implants, "spontaneous" fibrosis, and tumor-associated fibrotic changes.

IGF-II and IGFBP-6 regulate cellular contractility and proliferation in Dupuytren's disease

Dupuytren's disease (DD) is a common and heritable fibrosis of the palmar fascia that typically manifests as permanent finger contractures. The molecular interactions that induce the development of hyper-contractile fibroblasts, or myofibroblasts, in DD are poorly understood. We have identified IGF2 and IGFBP6, encoding insulin-like growth factor (IGF)-II and IGF binding protein (IGFBP)-6 respectively, as reciprocally dysregulated genes and proteins in primary cells derived from contracture tissues (DD cells). Recombinant IGFBP-6 inhibited the proliferation of DD cells, patient-matched control (PF) cells and normal palmar fascia (CT) cells. Co-treatments with IGF-II, a high affinity IGFBP-6 ligand, were unable to rescue these effects. A non-IGF-II binding analog of IGFBP-6 also inhibited cellular proliferation, implicating IGF-II-independent roles for IGFBP-6 in this process. IGF-II enhanced the proliferation of CT cells, but not DD or PF cells, and significantly enhanced DD and PF cell contractility in stressed collagen lattices. While IGFBP-6 treatment did not affect cellular contractility, it abrogated the IGF-II-induced contractility of DD and PF cells in stressed collagen lattices. IGF-II also significantly increased the contraction of DD cells in relaxed lattices, however this effect was not evident in relaxed collagen lattices containing PF cells. The disparate effects of IGF-II on DD and PF cells in relaxed and stressed contraction models suggest that IGF-II can enhance lattice contractility through more than one mechanism. This is the first report to implicate IGFBP-6 as a suppressor of cellular proliferation and IGF-II as an inducer of cellular contractility in this connective tissue disease.

Genome-wide analysis using exon arrays demonstrates an important role for expression of extra-cellular matrix, fibrotic control and tissue remodelling genes in Dupuytren's disease

Dupuytren's disease (DD) is a classic example of pathological fibrosis which results in a debilitating disorder affecting a large sector of the human population. It is characterized by excessive local proliferation of fibroblasts and over-production of collagen and other components of extracellular matrix (ECM) in the palmar fascia. The fibrosis progressively results in contracture of elements between the palmar fascia and skin causing flexion deformity or clawing of the fingers and a severe reduction in hand function. While much is known about the pathogenesis and surgical treatment of DD, little is known about the factors that cause its onset and progression, despite many years of research. Gene expression patterns in DD patients now offers the potential to identify genes that direct the pathogenesis of DD. In this study we used primary cultures of fibroblasts derived from excisional biopsies of fibrotic tissue from DD patients to compare the gene expression profiles on a genome-wide basis with normal control fibroblasts. Our investigations have identified genes that may be involved with DD pathogenesis including some which are directly relevant to fibrosis. In particular, these include significantly reduced expression levels of three matrix metallopeptidases (MMP1, MMP3, MMP16), follistatin, and STAT1, and significantly increased expression levels of fibroblast growth factors (FGF9, FGF11), a number of collagen genes and other ECM genes in DD patient samples. Many of these gene products are known to be involved in fibrosis, tumour formation and in the normal processes of tissue remodelling. In addition, alternative splicing was identified in some DD associated genes. These highly sensitive genomic investigations provide new insight into the molecular mechanisms that may underpin the development and progression of DD.

Penile traction therapy and Peyronie's disease: a state of art review of the current literature

In recent years, penile traction therapy (PTT) has gained considerable interest as a novel nonsurgical treatment option for men with Peyronie's disease (PD) and short penises. The current published literature suggests that selected cases of PD may benefit from a conservative approach with PTT, resulting in increased penile length and reduction of penile deformity. It appears to be safe and well tolerated but requires a great deal of patient compliance and determination. This article reviews the current literature pertaining to the use of PTT in men with PD, short penises and in the setting of pre- and postprosthesis corporal fibrosis.

The mechanical environment in Dupuytren's contracture determines cell contractility and associated MMP-mediated matrix remodeling

Matrix metalloproteinases (MMPs) are expressed in Dupuytren's contracture and play a role in matrix remodeling. We tested the role of tension on contractility and MMP expression in Dupuytren's nodule and cord cells. Cells were subjected to pre-determined loading patterns of known repeatable magnitudes (static load, unloading, and overloading) and tested for MMP gene expression (MMP-1, -2, -9, -13, and TIMP-1, -2) and force generation using a tension-culture force monitor. Matrix remodeling was assessed by addition of cytochalasin D and residual matrix tension was quantified. Nodule compared to cord and control cells demonstrate greater force generation and remodeling (p < 0.05). Nodule cells subjected to a reduced load and overloading led to threefold increase of MMP-1, -2, and -9 compared to static load, whilst cord and control cells only showed a twofold increase of MMP-9. Nodule cells subjected to overloading showed a twofold increase in TIMP-2 expression, whilst cord and control cells showed a twofold increase in TIMP-1 expression. Nodule cells differ from cord cells by increased force generation in response to changes in the mechanical environment and related MMP/TIMP-mediated matrix remodeling. In turn this may lead to permanent matrix shortening and digital contracture. Interventional therapies should be aimed at nodule cells to prevent contraction and subsequent permanent matrix remodeling.

Microarray analysis of Dupuytren's disease cells: the profibrogenic role of the TGF-β inducible p38 MAPK pathway

BACKGROUND

Dupuytren's disease (DD) is a nodular palmar fibromatosis that causes irreversible permanent contracture of fingers and results in the loss of hand function. Surgery still remains the only available solution for DD patients but cannot permanently cure the disease nor reduce high recurrence rates. With this rationale, we designed a study aimed at an improved understanding of the molecular mechanisms underlying DD. Our major focus was an analysis of the global gene expression profile and signalling pathways in DD cells with the aim of identifying novel biomarkers and/or therapeutic targets.

METHODS

Primary cells were cultured from surgically removed diseased and healthy tissue. Microarray expression analysis (HG-U133A array, Affymetrix) and qPCR was performed with total RNA isolated from primary DD cells. Mechanistic studies involving inhibition of p38 phosphorylation were performed on normal human fibroblasts' and primary DD cells' in vitro models. Expression of stem cell markers in primary fibroblasts/myofibroblasts was assessed as well.

RESULTS

We identified 3 p38MAPK signalling pathway regulatory genes, THBS1, GADD45α and NUAK1, all involved in cellular proliferation and production of the extracellular matrix proteins. Inhibition of the p38MAPK signalling pathway induced down-regulation of myofibroblast markers, α-smooth muscle actin and palladin. A stem-cell like subpopulation positive for CD90 marker was identified among primary DD cells.

CONCLUSION

The study reveals involvement of the p38 MAPK pathway as a possible signalling cascade in the pathogenesis of Dupuytren's disease. Moreover, a particular stem cell-like CD90(+) subpopulation was identified that might contribute to DD development.

Expression of MMP-2, TIMP-2, TGF-β1, and decorin in Dupuytren's contracture

To investigate the mechanisms underlying matrix deposition in Dupuytren's disease, the expression of gelatinase A (MMP-2), the tissue inhibitor of metalloproteinase-2 (TIMP-2), transforming growth factor beta 1 (TGF-β1), decorin (DCN), and periostin was studied. The level of relative MMP-2 activation was investigated using zymography. The mRNA expression of MMP-2, TIMP-2, TGF-β1, and DCN was detected using reverse transcription polymerase chain reaction (RT-PCR), while the presence of protein was detected using immunohistochemical (IHC) and Western blot techniques. The level of MMP-2 activation was significantly elevated in tissues with Dupuytren's contracture. RT-PCR demonstrated significantly higher expression of MMP-2, TIMP-2, TGF-β1, and DCN mRNA in the pathological tissues; and the IHC and immunoblotting studies revealed elevated expression of TGF-β1, DCN, and periostin. The balance between MMP-2 and TIMP-2 was disrupted in patients with Dupuytren's disease. TGF-β1, DCN, and periostin are involved in extracellular matrix (ECM) homeostasis in Dupuytren's contracture.

WNT2 locus is involved in genetic susceptibility of Peyronie's disease

INTRODUCTION

Peyronie's disease (PD) is a fibromatosis of the penis, with a pathology very similar to what is seen in the hand (palmar fascia) in Dupuytren's disease (DD). Recently, we performed a genome-wide association study and identified nine genetic loci containing common variants associated with DD. Seven of these loci mapped within or near genes of the canonical WNT pathway and each locus yielded relatively large odds ratios (ORs) for DD disease status.

AIM

Given the clinical overlap between PD and DD, we examined whether the nine DD susceptibility loci are also involved in PD.

METHODS

An association study was performed using a case/control design. From 2007 to 2010, we prospectively included 111 men who had been clinically diagnosed with PD. Control subjects (N = 490 males) were randomly drawn from a population-based cohort from the same region of the Netherlands. Allele frequencies in the 111 PD cases and 490 controls were compared using a 1-degree-of-freedom basic chi-square test. A P value < 0.05 after Bonferroni correction for the nine tested single nucleotide polymorphisms (SNPs) was considered statistically significant (i.e., P < 0.0056).

MAIN OUTCOME MEASURE

Association of genetic markers (SNPs) with PD.

RESULTS

We observed significant association with SNP rs4730775 at the wingless-type MMTV integration site family member 2 (WNT2) locus on chromosome 7 (P = 0.0015, OR 0.61), but found no evidence for the other eight loci being involved with PD despite the large effect size seen for some of these variants in DD. The WNT2 association was even more significant after we removed 15 patients with comorbid DD.

CONCLUSIONS

WNT2 is a susceptibility locus for PD and our finding provides evidence for a partly shared genetic susceptibility between PD and DD.