Temporal gene signature of myofibroblast transformation in Peyronie's disease: first insights into the molecular mechanisms of irreversibility

BACKGROUND

Transformation of resident fibroblasts to profibrotic myofibroblasts in the tunica albuginea is a critical step in the pathophysiology of Peyronie's disease (PD). We have previously shown that myofibroblasts do not revert to the fibroblast phenotype and we suggested that there is a point of no return at 36 hours after induction of the transformation. However, the molecular mechanisms that drive this proposed irreversibility are not known.

AIM

Identify molecular pathways that drive the irreversibility of myofibroblast transformation by analyzing the expression of the genes involved in the process in a temporal fashion.

METHODS

Human primary fibroblasts obtained from tunica albuginea of patients with Peyronie's disease were transformed to myofibroblasts using transforming growth factor beta 1 (TGF-β1). The mRNA of the cells was collected at 0, 24, 36, 48, and 72 hours after stimulation with TGF-β1 and then analyzed using a Nanostring nCounter Fibrosis panel. The gene expression results were analyzed using Reactome pathway analysis database and ANNi, a deep learning-based inference algorithm based on a swarm approach.

OUTCOMES

The study outcome was the time course of changes in gene expression during transformation of PD-derived fibroblasts to myofibroblasts.

RESULTS

The temporal analysis of the gene expression revealed that the majority of the changes at the gene expression level happened within the first 24 hours and remained so throughout the 72-hour period. At 36 hours, significant changes were observed in genes involved in MAPK-Hedgehog signaling pathways.

CLINICAL TRANSLATION

This study highlights the importance of early intervention in clinical management of PD and the future potential of new drugs targeting the point of no return.

STRENGTHS AND LIMITATIONS

The use of human primary cells and confirmation of results with further RNA analysis are the strengths of this study. The study was limited to 760 genes rather than the whole transcriptome.

CONCLUSION

This study is to our knowledge the first analysis of temporal gene expression associated with the regulation of the transformation of resident fibroblasts to profibrotic myofibroblasts in PD. Further research is warranted to investigate the role of the MAPK-Hedgehog signaling pathways in reversibility of PD.

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.

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.

Alternative Splicing of IGF1 Gene as a Potential Factor in the Pathogenesis of Peyronie's Disease

BACKGROUND/AIM

Peyronie's disease (PD) is a fibrotic entity for which the pathogenetic mechanism remains unclear and if resulting in severe deformity, its treatment is only surgical. In this study we investigated the possible role of insulin-like growth factor 1 (IGF1) expression in the pathogenesis of PD.

MATERIALS AND METHODS

Tissue samples were obtained from plaques of 24 patients with PD. The expression of IGF1 isoforms was investigated using quantitative real-time polymerase chain reaction and immunofluorescence.

RESULTS

All IGF1 isoform gene expression (Ea, Eb and Ec) were found significantly decreased in the affected tunica albuginea, compared to normal tunica albuginea, with Ec showing the greatest decrease. Staining of tissue sections with an antibody against IGF1Ec confirmed greater expression of IGF1Ec isoform in normal tunica albuginea.

CONCLUSION

The expression of all IGF1 alternative spliced isoforms is decreased in patients with PD, suggestive of its possible participation in the pathophysiology of PD.

Comparison of apoptotic gene expression profiles between Peyronie's disease plaque and tunica albuginea

BACKGROUND

The fibrotic plaques of Peyronie/s disease and other localized fibrotic conditions have been considered to be the result of an abnormal wound healing process. The potential role of regulatory disorders of apoptosis in abnormal wound healing may also play a role in the development of Peyronie's disease.

OBJECTIVES

To examine the phenomenon of apoptosis in Peyronie's disease, authors quantified differential levels of gene expression of apoptotic proteins, Fas, Fas Ligand, Bcl-2, p53, Caspase 3 and 8 in Peyronie's plaque and tunica albuginea.

MATERIAL AND METHODS

Eight patients with Peyronie's disease undergoing surgical correction of the curvature had biopsy specimens taken from both the Peyronie's plaque and normal tunica albuginea. Messenger RNA expression of the apoptotic proteins in the plaque and normal tunica was measured by reverse transcriptase PCR.

RESULTS

Apoptotic gene expression was lower than the housekeeping gene's in half of the tunica albuginea samples and two thirds of the plaque samples. Overall mRNA expressions in the plaque were not significantly different from the normal tunica albuginea.

CONCLUSIONS

The fibrotic plaques of Peyronie's disease and other localized fibrotic conditions have been considered to be the result of an abnormal wound healing process. The potential role of regulatory disorders of apoptosis in abnormal wound healing may also play a role in the development of Peyronie's disease. In this study, the lower expression of apoptotic genes may cause the persistence of collagen producing cells which were up-regulated for unknown reasons and consequently result in plaque formation. Similar expression levels of apoptotic genes in both tunica albuginea and Peyronie's plaques may be due to the generalized physiopathologic alterations in tunica albuginea that lead to plaque formation at a vulnerable region subjected to recurrent traumas.

Repeated intratunical injection of adenovirus expressing transforming growth factor-beta1 in a rat induces penile curvature with tunical fibrotic plaque: a useful model for the study of Peyronie's disease

This study was undertaken to establish a Peyronie's disease model with penile curvature by using recombinant transforming growth factor-beta1 (TGF-beta1) protein or adenovirus (ad-TGF-beta1). Four-month-old male Sprague-Dawley rats were divided into seven groups (n = 18 per group): G1 received a single injection of saline into the tunica albuginea (0.1 mL); G2, repeated injections of ad-LacZ (days 0, 3, and 6; 1 x 10(10) particles/0.1 mL respectively); G3, a single injection of recombinant TGF-beta1 protein (700 ng/0.1 mL); G4, repeated injections of recombinant TGF-beta1 protein (days 0, 3 and 6; 700 ng/0.1 mL respectively); G5, a single injection of low-dose ad-TGF-beta1 (1 x 10(10) particles/0.1 mL); G 6, a single injection of high-dose ad-TGF-beta1 (3 x 10(10) particles/0.1 mL); and G7, repeated injections of low-dose ad-TGF-beta1 (days 0, 3, and 6; 1 x 10(10) particles/0.1 mL respectively). Penile curvature was evaluated 30, 45 and 60 days after treatment, and the penis was then harvested for histological examination. Repeated injection of low-dose ad-TGF-beta1 not only induced fibrous scar in the tunica, which lasted up to 60 days after injection, but also resulted in significant penile curvature by artificial erection test 45 days after treatment. A peculiar histological finding in this group was trapping of inflammatory cells in the tunica, subsequent fibrosis, and formation of cartilage and calcification as well as loss of elastin fibres. This model involving repeated injection of ad-TGF-beta1 may contribute to further investigation of the pathogenesis of Peyronie's disease and the development of new therapeutics targeting this pathway.

Is There a Role for Proteomics in Peyronie's Disease?

INTRODUCTION

Peyronie's disease (PD) continues to be a major source of sexual dysfunction among the 3-9% of affected men. The challenge in treating PD is determining the natural history and clinical course for the individual patient. Currently, there exists no reliable means to predict whether a penile plaque of PD will progress, regress, or remain stable. This represents a significant deficiency in contemporary management, one that may be addressed with newer technologies such as proteomic profiling.

AIM

This review assesses the potential use of protein alterations measured by various novel technologies, to predict progression, regression, or stabilization of PD in an affected individual.

METHODS

A comprehensive literature review of the past decade in the field of gene profiling and protein expression of PD was performed.

MAIN OUTCOME MEASURES

A critical analysis of the existing worldwide literature evaluating surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS or SELDI) and other proteonomic techniques.

RESULTS

SELDI and other technologies can provide the clinician with innovative data indicating the presence of unique individual factors that act to suppress or promote the fibrotic process in PD. Determining the clinical implications of altered protein expression in an individual is not yet defined.

CONCLUSIONS

The area of proteomics has begun to revolutionize the study of medicine in the postgenomic era, by allowing researchers to study the role that proteins play in health and disease. Applying this knowledge clinically has already led to innovative discoveries in early cancer detection in a number of malignancies, including prostate, ovarian, and bladder. Prior to the widespread use and acceptance of proteomic technology in PD, a critical assessment of its therapeutic and diagnostic value will be required.

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

OBJECTIVES

To compare the gene expression alterations in human Peyronie's disease (PD) and Dupuytren's disease (DD) to determine whether they share a common pathophysiology. Multiple mRNA expression profiles of human PD have previously shown that genes that regulate fibroblast replication, myofibroblast differentiation, collagen metabolism, tissue repair, and ossification are involved. DD, a palmar fascia fibrosis, may be associated with PD.

METHODS

Total RNA samples from PD plaques, normal tunica albuginea, Dupuytren's nodules, and normal palmar fascia (nine samples per group) were subjected to differential gene expression profile analysis (Clontech Atlas DNA microarray) comparing PD with tunica albuginea and DD with normal palmar fascia. Changes of more than 2.0 in PD and DD compared with tunica albuginea and normal palmar fascia, respectively, were recorded. Reverse transcriptase-polymerase chain reactions were performed for some genes whose expression was altered in PD.

RESULTS

Some of the gene families upregulated in both PD and DD were (a) collagen degradation: matrix metalloproteinase (MMP), with MMP2 and MMP9, and thymosins (MMP activators), with TMbeta10 and TMbeta4; (b) ossification: osteoblast-specific factors (OSFs) OSF-1 and OSF-2 (DD only); and (c) myofibroblast differentiation: RhoGDP dissociation inhibitor 1. The genes upregulated in PD only were decorin (an inhibitor of transforming growth factor-beta1 and a part of fibroblast replication/collagen synthesis) and early growth response protein. Reverse transcriptase-polymerase chain reaction confirmed these changes.

CONCLUSIONS

These data demonstrate that the pattern of alterations in the expression of certain gene families in PD and DD is similar, suggesting that they share a common pathophysiology and may be amenable to the same therapeutic regimens.

Alpha-1-Antitrypsin Levels and Genetic Variation of the Alpha-1-Antitrypsin Gene in Peyronie’s Disease

OBJECTIVES

Alpha-1-antitrypsin (alpha1-antitrypsin) is a major protease inhibitor controlling tissue degradation. Reduced alpha1-antitrypsin levels could result in a change of collagen metabolism. Previous studies have described decreased alpha1-antitrypsin levels in patients with Peyronie's disease. However, only a small number of patients were analyzed, and the reason for the decreased alpha1-antitrypsin levels remained unclear. This study investigated prospectively the levels of alpha1-antitrypsin in patients with Peyronie's disease, as well as genetic variation in the coding region of the alpha1-antitrypsin gene.

METHODS

Alpha1-antitrypsin levels were determined prospectively in 94 patients with Peyronie's disease and compared to healthy controls. Analysis of the alpha1-antitrypsin gene (S, Z variants; single nucleotid polymorphisms [SNPs]: T-395A, M2, M3, G6118A) was done in 141 Peyronie's patients including 43 patients with investigated alpha1-antitrypsin serum levels and compared to healthy controls.

RESULTS

In patients with Peyronie's disease, the alpha1-antitrypsin levels seemed to be decreased significantly compared to healthy controls. However, in the age matched approach no significant differences occurred. Moreover, a significant (p < 0.002) decrease of the alpha1-antitrypsin level with increasing age was observed, explaining the initial differences between the two groups. In confirmation with these findings, no significant association of the alpha1-antitrypsin gene variants with Peyronie's disease was detectable.

CONCLUSIONS

The results of this study do not indicate a significant association between Peyronie's disease and decreased alpha1-antitrypsin levels. Low alpha1-antitrypsin levels in Peyronie's patients are, rather, an age-related phenomenon, as revealed by the comparison with aged matched healthy controls. The decrease of the alpha1-antitrypsin serum level with increasing age has not been described before.

Chromosomal instability is demonstrated by fibroblasts derived from the tunica of men with Peyronie's disease

Peyronie's disease is a fibrotic disorder, a condition characterized by cellular proliferation and excess extracellular matrix production. Previous work in related conditions has demonstrated chromosomal instability. This investigation was undertaken to analyze fibroblasts derived from Peyronie's disease tunical tissue for abnormalities of chromosome number and progression of cytogenetic aberrations during cell culture. Tunical tissue was excised from men with Peyronie's disease from both plaque and nonplaque tissue and cells were explanted in culture. Control cells were derived from both neonatal foreskins and normal tunica from men with congenital penile curvature. Fluorescent in situ hybridization was used to probe for chromosomes 7, 8, 17, 18, X and Y. Control cells demonstrated normal copy number for all chromosomes analyzed. In contrast, Peyronie's disease plaque-derived fibroblasts demonstrated frequent aneusomies in chromosomes 7, 8, 17, 18 and X and recurrent deletions of chromosome Y. Peyronie's disease nonplaque tunica-derived fibroblasts demonstrated infrequent chromosomal changes early in culture; however, with repeated passaging the majority of cell cultures demonstrated aneusomies in at least one chromosome. These data indicate that Peyronie's disease plaque-derived fibroblasts have consistent aneusomies even at early passage and that nonplaque tunica-derived cells from men with Peyronie's disease also demonstrate chromosomal instability. This suggests that the tunica albuginea of men with Peyronie's disease may be predisposed to undergoing unregulated fibrosis. These findings confirm the transformed nature of the Peyronie's disease tunical fibroblasts studied in this analysis. While the etiology of these findings is not clear, it is likely that these pathobiological characteristics contribute to the pathophysiology of this disease process.

[Gene expression profiles and effects of transforming growth factor-beta1 intervention in Peyronie's disease]

OBJECTIVE

To demonstrate molecular insight into the pathology of Peyronie's disease (PD). A preliminary profile of differential gene expression between the PD plaque and control tunica albuginea was obtained with DNA microarrays. Also, to investigate the effect of intervention in PD cells, transforming growth factor-beta1 (TGF-beta1) was recruited to treat PD cell lines.

METHODS

Three PD plaques and control tunica albugineas were constructed and studied. cDNA probes were prepared from RNA isolated from those cells and hybridized with the Clontech Atlas 3.6 Array. Relative changes of greater than 2.0 defined up-regulation and down-regulation, respectively. The expression of selected individual gene MCP-1 and the effect of TGF-beta1 on MCP-1 were analyzed by reverse transcriptase-polymerase chain reaction.

RESULTS

Some up-regulated genes in the PD plaque detected by the Clontech assay were screened, one of them was monocyte chemotactic protein. One involved the pathogenesis of PD as a downstream gene and responded to the TGF-beta1 treatment but not CTGF. The results were also confirmed by TR-PCR in all the types of cell.

CONCLUSIONS

The cell lines from plaque tissue and normal tunica from men with PD were successfully established. The findings indicate a potential role for MCP-1 over expression in the pathogenesis of PD as a downstream gene regulated by some genes and could be a new therapeutic target in PD. The information may allow a better understanding of the basic mechanisms involved in the etiology and pathogenesis of PD. Furthermore, it may permit some strategies of therapeutic interventions combine routine methods with Chinese herbal medicine.

Peyronie's disease: a review

PURPOSE

We provide a current review of Peyronie's disease.

MATERIALS AND METHODS

We reviewed the world peer reviewed literature on the pathology, pathogenesis, diagnosis and treatment of Peyronie's disease.

RESULTS

The incidence of Peyronie's disease has continuously increased during the last 30 years. However, fewer patients need prosthesis surgery as the sole treatment option because of earlier diagnosis, improved medical therapy, refinement in surgical technique and better understanding of the basic sciences of the disease.

CONCLUSIONS

Currently patients with Peyronie's disease have had improvements in prognosis and experienced an expansion of the available therapeutic options.

Prospective analysis of single nucleotide polymorphisms of the transforming growth factor beta-1 gene in Peyronie's disease

PURPOSE

The detection of increased expression of transforming growth factor beta-1 (TGF-beta1) in Peyronie's disease plaques and the possibility of initiating a Peyronie's disease-like condition by intratunical injection of a synthetic heptopeptide with TGF-beta-like activity in an animal model has provided evidence for the central role of this cytokine in the pathogenesis of this entity. Recently 2 defined single nucleotide polymorphisms in the coding region of the TGF-beta1 gene have been described that are associated with different levels of TGF-beta1 production. Based on these data we prospectively investigated the genetic association of distinct TGF-beta1 genotypes with Peyronie's disease.

MATERIALS AND METHODS

DNA samples from 111 consecutive patients with idiopathic Peyronie's disease and 100 controls were genotyped for the 2 defined dimorphic single nucleotide polymorphisms T869C and G915C in the coding region of the TGF-beta1 gene using allele specific polymerase chain reaction.

RESULTS

We found an increased frequency of the homozygous genotype of the single nucleotide polymorphism G915C in patients with Peyronie's disease compared with healthy controls (89.2% versus 79%, p = 0.04). However, there were no significant differences in allele frequencies of the single nucleotide polymorphism T869C.

CONCLUSIONS

Experimental data from other investigators have shown that TGF-beta1 has an important role in the etiopathology of Peyronie's disease. Our results indicate that the homozygous wild type of the G915C single nucleotide polymorphism in the coding region of the TGF-beta1 gene, which was recently associated with elevated TGF-beta1 production and pulmonary fibrosis, may influence the predisposition to Peyronie's disease. However, it does not represent a major genetic risk factor.

Gene expression in Peyronie's disease

Currently, surgical intervention is the only efficacious treatment for Peyronie's disease (PD), a fibromatosis of the tunica albuginea of the penis. Therapies based on the molecular pathways for this disease could provide alternatives to surgical treatment but only recently has the pathophysiology of the Peyronie's disease plaque been investigated at the molecular level. In this review, we examine the current knowledge of gene expression in the PD plaque and the relationship of PD with other fibrotic conditions such as Dupytren's disease. TGFbeta1, along with other growth factors, pro-fibrotic genes, and collagen, are expressed in fibroblasts and myofibroblasts. Myofibroblasts are normally involved in wound contracture and largely eliminated via apoptosis during the late stages of wound remodeling. In the PD plaque, however, these cells persist and may play an important role in the PD plaque fibrosis. The expression levels of TGFbeta1 and pro- and anti-fibrotic gene products, along with the nitric oxide/reactive oxygen species (NO/ROS) ratio in the tunica albuginea, appear to be essential for the formation and progression of the PD plaque and effect the expression of multiple genes. This can be assessed with the recently developed DNA-based chip arrays and results with the PD plaque have been encouraging. OSF-1 (osteoblast recruitment), MCP-1 (macrophage recruitment), procollagenase IV (collagenase degradation), and other fibrotic genes have been identified as being possible candidate regulatory genes. Finally, possible therapeutic avenues for gene-based therapy in the treatment of PD are discussed that may eventually reduce the need for surgical intervention.

Gene expression profiles in the Peyronie's disease plaque

OBJECTIVES

To provide molecular insight into the pathophysiology of Peyronie's disease (PD), a preliminary profile of differential gene expression between the PD plaque and control tunica albuginea was obtained with DNA microarrays.

METHODS

Seven PD plaques and five control tunica albugineas were studied. cDNA specimens were prepared from RNA isolated from one calcified PD plaque and one control tissue and hybridized with the Clontech Atlas 1.2 Array. Another set of plaque and control RNA samples was hybridized with the Affymetrix GeneChip. Relative changes of greater than 2.0 defined up-regulation and down-regulation, respectively. RNA from the remaining tissues was used to determine, by reverse transcriptase-polymerase chain reaction and Western blot analysis, the expression of selected individual genes.

RESULTS

Some of up-regulated genes in the PD plaque detected by the Clontech assay were pleiotrophin, monocyte chemotactic protein 1, and early growth response protein, which are involved in osteoblast recruitment, inflammation, and fibroblast proliferation, respectively. Ubiquitin and Id-2, which are involved in tissue remodeling, were down-regulated. The Affymetrix DNA chips identified the up-regulation of elastase (involved in elastic fiber degradation) and the myofibroblast markers alpha and gamma-smooth muscle actin, desmin, and others, as well as the down-regulation of collagenase IV and transforming growth factor-beta modulators. Four of the five genes selected for reverse transcriptase-polymerase chain reaction and Western blotting confirmed the DNA microarray results.

CONCLUSIONS

In the PD tissue, the genes involved in collagen synthesis, myofibroblast differentiation, tissue remodeling, inflammation, ossification, and proteolysis are up-regulated, and the genes that inhibit some of these processes and collagenase are down-regulated.

New advances in Peyronie's disease

The formation of Peyronie's disease plaques is a process that seems to involve a cascade of genetic, structural and immunologic events. Clinical manifestations include penile deformity and possible erectile dysfunction. Rational strategies have been forthcoming, with both minimally invasive and surgical treatments of Peyronie's disease available. This article reviews and updates current scientific and clinical advances in Peyronie's disease.

The genetics and immunology of Peyronie's disease

Peyronie's disease (PD) is a condition characterized by localized and often progressive fibrosis and scarring of the penis. This condition has an unknown etiology although several hypotheses have been proposed. These include traumatic, immunologic and genetic causes. We studied the genetics and immunology of PD using both molecular biologic and molecular genetic techniques. Men (n=283) with PD were identified by retrospective chart review of one physician's office practice. These men were contacted by telephone and asked to submit to an interview and blood test for genetic studies. Simultaneously, tissue and cells collected in the laboratory were examined by Western and Northern blot analysis for examination of protein and RNA for expression of HLA. Of the first 107 men contacted, 24 were available and consented to interview and blood testing. The mean age was 60.3 y with an average duration of PD of 4.9 y. One patient had a family history of PD while no patients had Dupuytren's contracture. Twenty patients were considered to have primary disease while four were secondary. Eleven patients had tissue prepared for Northern blot analysis and nine patients were the subject of Western blot analysis. All tissue, both Peyronie's and control expressed class I MHC while no tissue expressed class II MHC. The expression of mRNA of class I MHC was equal for Peyronie's and control patients while the expression at the protein level was less in the PD patients. We conclude that PD may have multiple etiologic agents. One cannot exclude a class II MHC association but in our population, HLA DQ is not expressed. Class I MHC may be involved as the expression of class I MHC protein is different in Peyronie's patients than in controls. Genetic studies are ongoing. International Journal of Impotence Research (2000) 12, Suppl 4, S127-S132.

Microsatellite alterations and loss of heterozygosity in Peyronie's disease

PURPOSE

In the present study, we tested the hypothesis that microsatellite alterations (MSI) and loss of heterozygosity (LOH) are associated with Peyronie's disease. To test this hypothesis, we analyzed samples from patients with Peyronie's for MSI and LOH on chromosomes 3, 8 and 9 using 20 different genetic markers.

MATERIALS AND METHODS

DNA was isolated from the penile fibrotic plaque, amplified using PCR, and analyzed for MSI and LOH on chromosomes 3, 8 and 9 using 20 different polymorphic markers (D3S1228, D3S1298, D3S1560, D3S1745, D3S2396, D3S647, D8S133, D8S255, D8S259, D8S260, D8S262, D8S285, D8S298, D8S507, D8S528, D9S162, D9S171, D9S1747, D9S1748, and D9S273). Only 10 primers (D3S1560, D3S647, D3S1298, D8S262, D8S260, D8S528, D9S171, D9S1747, D9S273 and D9S1748) showed MSI and LOH in Peyronie's samples. Microsatellite alterations and LOH were analyzed by a PCR-based technique developed in our laboratory.

RESULTS

This study demonstrates a high frequency of MSI and LOH in Peyronie's disease. Fourteen of 35 cases (40%) showed MSI at a minimum of one locus, 6 of 35 cases (17%) at a minimum of 2 loci and three of 35 (8.5%) cases at three or more loci. D9S273 locus showed highest MSI when compared with other loci examined in this study. For LOH, 14 of 35 cases (40%) were observed at a minimum of one locus, 5 of 35 cases (14%) at minimum of two loci and one out of 35 cases (2.8%) showed LOH at three or more loci. The D3S1560 and D9S171 loci showed highest LOH when compared with all other loci examined in this study.

CONCLUSION

This is the first report demonstrating that a high frequency of MSI and LOH is associated with Peyronie's disease, suggesting their role in the pathogenesis of this disease.

A case-control study on risk factors for Peyronie's disease

The aim of this study was to investigate the relationship between history of selected diseases, genital traumas, and Peyronie's disease. A hospital-based case-control study was conducted at the Andrologic and Surgical Outpatient Units of the Policlinico Gemelli, Rome, where 134 men with Peyronie's disease and 134 male controls were interviewed. The association between Peyronie's disease and selected characteristics was estimated by means of odds ratios (OR) and 95% confidence intervals (CI). Patients who underwent invasive procedures on the penis (i.e., urethral catheterization, cystoscopy, and transurethral prostatectomy) had a 16-fold increased risk for Peyronie's disease (OR = 16.1, 95% CI: 1.8-142), while a nearly three-fold increase was observed among patients who had genital and/or perineal traumatisms (95% CI: 1.0-7.1). A history of urethritis, uricacidemia, and lipoma was also significantly associated with an increased risk for Peyronie's disease. Twenty-one percent of the cases and none of the controls were affected by Dupuytren's contracture, and 4% of cases and none of the controls reported familial history for Peyronie's disease. The frequency of inflammatory or fibromatous lesions of the genital tract of the partner was significantly higher in men with Peyronie's disease than among controls. These results were consistent when performing a stratified analysis according to the type of controls (i.e., controls affected by urologic or by digestive conditions) to rule out the potential effect of recall bias. The findings of the study lend support to clinical reports stressing the importance of genital traumatisms and genetic conditions in the development of Peyronie's disease.

Is there an immunogenetic basis for Peyronie's disease?

PURPOSE

Despite numerous studies, there has been no definitive HLA association with Peyronie's disease. Results of available studies have been reviewed and compared to determine if the cumulative evidence supports any immunogenetic, HLA association with Peyronie's disease.

MATERIALS AND METHODS

Data from reports of HLA associations with Peyronie's disease were reanalyzed by categories of reported HLA class I or class II antigens in comparison with recently available large population analysis of the frequencies of these antigens in the normal population. Data were also considered by whether they were derived from population or family analyses.

RESULTS

The results of 4 series of patients testing an association of Peyronie's disease with the HLA class I antigens, in particular the B7 related antigens, were contradictory. A B7 association was not confirmed in 2 larger series and, in fact, the B7 related antigens were observed in frequencies expected in a normal population, suggesting that the associations observed in the smaller series were due to chance. An association with the HLA class II antigen, DQ2, was found in 1 of the larger series. Reported family studies suggest a genetic basis for Peyronie's disease but do not indicate a gene closely linked to the HLA complex.

CONCLUSIONS

Considering all available data, Peyronie's disease appears to be multifactorial in pathogenesis. Because Peyronie's disease is likely heterogeneous and because available studies have analyzed serologically defined HLA antigens, future studies to define HLA alleles molecularly and to characterize patient subgroups may clarify an immunogenetic basis.

The genetic and bacteriological aspects of Peyronie's disease

PURPOSE

Peyronie's disease has been associated with HLA tissue types, including HLA-A1, DR3, DQw2 and HLA-B7 cross-reactive group antigens which include HLA-B27. This association was tested as was the process of molecular mimicry where the host HLA surface antigen cross-reacts with a microorganism.

MATERIALS AND METHODS

HLA tissue typing was performed on 51 white patients with Peyronie's disease, of whom 15 also had Dupuytren's contracture of the hand. Fecal, urine and urethral samples were taken from patients with Peyronie's disease who had proved penile inflammation on biopsy. The samples were cultured for species of Campylobacter, Shigella, Salmonella, Yersinia, Chlamydia and gonococcus, all known to cross-react with the HLA-B27 surface antigen. Antibodies to Klebsiella species, Proteus species and Escherichia coli were also assessed in the sera of 65 patients with Peyronie's disease.

RESULTS

A significant association between Peyronie's disease and HLA-B27 was found (p = 0.02). The remaining antigens of the HLA-B7 group were not significantly associated with the disease individually (HLA-B7 p > 0.2, HLA-B22 p > 0.6, HLA-B40 p > 0.7) or as a group (p = 0.69). The previously found associations did not reach significance in this study (HLA-A1 p > 0.5, HLA-B8 p > 0.2, HLA-Cw7 p = 0.1, HLA-DR3 p > 0.4, HLA-DQ2 p > 0.4). Cultures for all enteric and urethral organisms were negative, and patients with Peyronie's disease did not have elevated serum titers of anti Klebsiella, anti Proteus or anti E. coli antibodies.

CONCLUSIONS

Although there is an association between Peyronie's disease and HLA-B27, molecular mimicry does not occur with the organisms tested, and an infectious agent has not been found in this study.

HLA antigens in Peyronie's disease

This study presents data on HLA phenotypes of 52 unrelated patients suffering from idiopathic Peyronie's disease. This first investigation on HLA class II antigens detected an association of HLA-DR3 and -DQw2 in this disorder. HLA typing was done from ACD-stabilized peripheral blood using the modified lymphocytotoxicity test. Antigen frequencies of the patient group were compared with those of healthy individuals of the local population. There were no deviations of frequencies for antigens of the B7 cross-reacting group as described in earlier studies. In addition none of the other class I antigens (HLA-A, -B, -C) showed any significant deviation in frequencies after correction of p values. Regarding class II antigens HLA-DR3 was detected in the patient group in 33.3% compared with 16.0% of the control population (corrected p < 0.05). The closely linked antigen DQw2 was found in 58.8 compared with 31.2% (corrected p < 0.005). Not only genetic factors can be stated by these findings. As HLA-DR3 and -DQw2 are known to be the typical associated antigens of organospecific autoimmune disorders, this suggests possible autoimmunological factors in this disorder of otherwise unknown etiology.

HLA association of idiopathic Peyronie's disease: an indication of autoimmune phenomena in etiopathogenesis?

HLA typing for class I and class II antigens was done in 52 unrelated patients suffering from idiopathic Peyronie's disease. The controversially discussed association with the HLA-B7 cross-reacting group could not be confirmed. Marked deviations of antigen frequencies were observed for HLA-A1, B8, Cw7, DR3 and DQw2 compared to healthy local controls. After correction of p-values, A1 (pc less than 0.05) and DQw2 (pc less than 0.01) remained significant. A possible association of Peyronie's disease with markers of the HLA-A1, B8, Cw7, DR3, DQw2 haplotype, as first described here, would suggest autoimmunological factors in this disorder of otherwise unknown etiopathogenesis.

Multiple clonal chromosome abnormalities in Peyronie's disease

Numerical and structural chromosome aberrations were found in cell plaque metaphases from 9 of 14 patients with Peyronie's disease. In two cases there was evidence of clonal evolution for some of the chromosomal aberrations observed. The Y chromosome was the most frequently involved in numerical changes. Four of 9 cases with abnormal karyotype showed more than one abnormal, cytogenetically unrelated clone. Our findings suggest the possibility of a multiclonal origin for this benign tumor, and confirm the presence of chromosome instability in this cell growth disorder.

Chromosome abnormalities in Peyronie's disease

Peyronie's disease is a localized and progressive fibrosis of unknown etiology that affects the tunica albuginea of the penis. We examined cytogenetically cell cultures derived from plaque, adjacent tunica, dermis and lymphocytes in patients with Peyronie's disease, and compared the results to cell cultures established from the tunica albuginea of control patients. Chromosomal abnormalities were detected in 9 plaque-derived cell cultures from 7 of 12 Peyronie's disease patients (58 per cent). Cells cultured from adjacent tunica, dermis and lymphocytes from the same patients were karyotypically normal, as were cultures derived from control (chordee and penile scar) patients. Chromosomal aberrations consisted of 5 numerical changes and 4 structural rearrangements, and included chromosomal additions (trisomy 7 and trisomy 8), deletions (45X,-Y), reciprocal translocations and inversions or markers. In 2 instances cultures derived from plaque tissue contained 2 independent chromosomal abnormalities. The apparently random chromosomal changes associated with Peyronie's disease suggests that karyotypic instability may be a common feature of cells within the plaque. It presently is unclear whether this finding represents multiple pathways for the development of Peyronie's disease or secondary consequences of Peyronie's disease.

Factors associated in the aetiology of peyronie's disease

In a retrospective study of 408 patients with Peyronie's disease 8 (1.9%) patients gave a positive family history for the condition. Sixty-three (15.4%) patients had a Dupuytren's contracture and trauma was considered to be an aetiological factor in 88 (21.5%) patients. One hundred and twenty-two (29.9%) patients had evidence of atherosclerosis and this is thought to be a factor in the pathogenesis of the disease. Peyronie's disease is not a single disease entity and is associated with many aetiological factors.

Identification of an inherited form of Peyronie's disease with autosomal dominant inheritance and association with Dupuytren's contracture and histocompatibility B7 cross-reacting antigens

Peyronie's disease is an inflammatory disorder with no confirmed etiology. We have documented the familial transmission of the disease as an autosomal dominant trait in 3 pedigrees. The occurrence of Dupuytren's contracture in 7 of 9 (78 per cent) affected individuals, which is a significant increase over the average 0 per cent reported in sporadic cases, suggests that both of these fibrosing disorders are pleiotropic effects of the same gene in these families. Similarly, the histocompatibility B7 cross-reacting antigens were present in 90 per cent of the patients with Peyronie's disease. Additional studies, including careful family histories and histocompatibility antigen typing, are necessary to elucidate the role of histocompatibility antigens as a relative risk factor.

Peyronie's disease: a newly recognized autosomal-dominant trait

Peyronie's disease, a connective tissue disorder of unknown cause, is characterized by the formation of thickened fibrous plaques on the dorsum of the penis. It often occurs simultaneously with other fibrotic changes, most notably Dupuytren's contracture of the hands or feet. There are no previous reports suggesting inheritance of this syndrome; however, Willscher et al reported an association between Peyronie's disease and antigens of the HLA-B7 cross-reacting group. Family studies were undertaken when three patients reported similarly affected first-degree relatives. One kindred showed father-to-son transmission of Peyronie's disease with Dupuytren's contracture in three generations. Pedigree analysis of the three families suggests that Peyronie's syndrome is a male-limited, autosomal-dominant trait. Antigens of the HLA-B7 cross-reacting group occurred in all three kindreds; however, the data ruled out close linkage of the disease and HLA.