Pathogenesis Of Lichen Sclerosus Research Articles

PD35-11 EPITHELIAL DIFFERENTIATION IS ALTERED IN URETHRAL LICHEN SCLEROSUS

You have accessJournal of UrologyCME1 Apr 2023PD35-11 EPITHELIAL DIFFERENTIATION IS ALTERED IN URETHRAL LICHEN SCLEROSUS Ethan Richmond, Caleb Sokovich, Wei Huang, Chad Vezina, and Matthew D Grimes Ethan RichmondEthan Richmond More articles by this author , Caleb SokovichCaleb Sokovich More articles by this author , Wei HuangWei Huang More articles by this author , Chad VezinaChad Vezina More articles by this author , and Matthew D GrimesMatthew D Grimes More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003333.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Lichen sclerosus (LS) is an idiopathic chronic inflammatory disease of the genital epithelium resulting in fibrosis and severe urethral stricture disease in affected men. Epithelia are subdivided into basal, intermediate, and superficial cell layers which are defined by protein expression patterns. Loss of basal cell differentiation is a feature of other fibrotic disorders but have not been studied in the urethra or LS. The proteins keratin 5 (KRT5) and p63 have been reliably established as basal cell markers in urothelium. Therefore, we hypothesized that urethral epithelium affected by LS would have decreased basal expression of KRT5 and p63. METHODS: Urethral tissue after urethral biopsy or urethroplasty was examined by a genitourinary pathologist to determine LS status. Using multiplexed fluorescent immunohistochemistry, KRT 5, CD45, p63, and DAPI were stained and three epithelial regions imaged per specimen. Using QuPath analysis software, the epithelium was segmented into basal and luminal compartments and relative abundance (RA) of each primary antibody was measured (number of positive cells/number of nucleated cells). RA was compared with respect to LS status and basal/luminal compartment using a Mann-Whitney U test. RESULTS: We analyzed 14 slides (n=7 LS, n=7 non-LS). The RA of KRT5 and p63 positive cells were similar with respect to epithelial versus basal compartment and LS status. However, we noted a change in patterning such that LS tissues displayed a shift of KRT5 and p63 expression from the basal to the luminal epithelium. To quantify this, we compared the ratio of basal to luminal KRT5 and p63 expression and dichotomized this as “basal predominant” (>1) or “luminal predominant” (<1). LS urethra were significantly more likely to have luminal predominant expression of p63 and KRT5 compared to non-LS (p=0.03, p=0.03) (Figure 1). CONCLUSIONS: We identified a change in expression pattern of basal epithelial markers (KRT5 and p63) in LS urethra. Altered epithelial differentiation is seen in other inflammatory diseases and may be implicated in the pathogenesis of LS. Source of Funding: K12DK100022NIH/NIDDK © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e978 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ethan Richmond More articles by this author Caleb Sokovich More articles by this author Wei Huang More articles by this author Chad Vezina More articles by this author Matthew D Grimes More articles by this author Expand All Advertisement PDF downloadLoading ...

Lichen sclerosus: A C5B-9 mediated chronic microvascular injury syndrome potentially reflective of common adult comorbidities

Lichen sclerosus (LS) is a cutaneous disease of unknown etiology that often involves the vulva or foreskin but also can affect extragenital sites. Regardless of the anatomic site, the histomorphology and presumably pathogenesis are similar. Perhaps a clue to the pathophysiology of LS lies in its frequent association with morphea, specifically, when occurring in an extragenital context. In our experience a striking feature evident in established lichen sclerosis (LS) is one of superficial vascular drop out whereby residual vessels exhibited endothelial cell necrosis and microvascular basement membrane zone thickening, the latter reflective of antecedent episodes of microvascular injury. We sought to understand the pathophysiology that underlies the distinct vascular changes and in doing so, shed light on the pathogenesis of LS. We examined 44 cases of LS over a period of 2019 to 2021. We were able to obtain past medical histories in 34 of the 44 cases. Regarding pathological assessment, the predominant focus was on microvascular changes. We assessed the role of C5b-9 mediated vascular injury in the pathogenesis of the vasculopathy and enhanced type I interferon signaling in vessels given the morphologic semblance to the select interferonopathy syndromes, namely fibrosing dermatomyositis and Kohlmeier Degos disease. We examined the expression of CMV DNA and protein based on prior observations in an earlier study that isolated early protein expression in the microvasculature in the setting of LS and scleroderma. From a clinical perspective, the most striking association was an older age at the time of diagnosis (mean age of 62 years and median age of 61.5 years) and the presence of vascular comorbidities of diabetes, hypertension, and hyperlipidemia in almost 80% of cases. All cases showed significant microvascular changes in the superficial corium with the most frequent findings being those of significant basement membrane zone reduplication and vascular drop out. A number of cases showed prominent microvascular deposits of C5b-9 in the zone of hyalinizing fibrosis or subjacent to the discernible table of fibroplasia in the absence of enhanced type I interferon signaling. In no case were there viral cytopathic changes associated with CMV affecting the endothelium. The studies that encode CMV DNA or protein did not show a significant role for CMV reactivation in endothelium in the majority of the studied cases. It is concluded that the pathophysiology of LS includes a microvascular injury syndrome within the papillary dermis. The mechanism of endothelial cell injury is complement mediated at least in part and could reflect an adaptive immune response targeting endothelium indicative of classic complement pathway activation when coexisting with morphea or occurring in younger individuals. A non-immune based endothelial dysfunction and complement mediated injury unrelated to antibody driven classic complement pathway activation are more likely pathogenetically in the setting of certain diseases like diabetes mellitus and hypertension. Vascular drop out can be explained by the diminished endothelial progenitor pool needed to repopulate the damaged microvessels in certain settings like hypertension and diabetes.

Патогенез генитального склероатрофического лихена: потенциальные генетические и иммунные маркеры развития

Lichen sclerosus is a hard-to-diagnose chronic inflammatory skin disease that is difficult to treat; it significantly reduces patient’s quality of life and is associated with a high risk of genital tract disorders and genital cancer development. Mechanisms of autoimmunity, endocrine disorders, infectious agents, and genetic predisposition are considered as prognostic factors for lichen sclerosus. The search for pathogenetic markers of lichen sclerosus development in recent years has been in the area of investigating immunological factors and the genes encoding them, which include p53, p16IINK4, p27Kip1, EMC1, FOXO3, CDKN1B, galectin-7, interleukins-6 and -10, microRNA, tumor necrosis factor-α, and collagen types I, III, V. These markers are potential therapeutic targets requiring further study and analysis and may form the basis for understanding the true etiology and pathogenesis of lichen sclerosus. Key words: extracellular matrix protein, galectin-7, vulvar lichen sclerosus, interleukins, microRNA, oxidative stress, lichen sclerosus, tumor necrosis factor-α

Vulvar Lichen Sclerosus et Atrophicus in girls

The review is devoted to diagnosing and treating lichen sclerosus (LS), a chronic inflammatory dermatosis with a predisposition to lesions of the anogenital region in girls. An essential role in the aetiology of this form of pathology is attributed to genetic mutations, injuries, infections and autoimmune diseases, and hormonal and local factors. The peak incidence is observed in 4-6 year girls, accounting for 7-15% of all cases of vulvar LS. The main goal of pharmacotherapy for vulvar LS is to relieve clinical symptoms and prevent scarring and adhesions. The authors analyzed international and domestic publications from 2017 to 2021. PubMed and Google Academy databases were used for the search, keywords: lichen sclerosus, girls. The retrospective and prospective cohort, randomized clinical trials, case series and literature reviews, and clinical guidelines were considered. Our review presents modern data on the diagnosis and treatment of SL in girls, which will be useful for both pediatric gynecologists and doctors of related specialties. The first symptoms of LS are usually nonspecific and are misdiagnosed by non-profile specialists. Some symptoms of LS may disappear spontaneously after menarche, and the course of the disease may be latent. This is why it is generally accepted that the epidemiology of LS is underestimated. Despite this, it can be assumed that the etiology and pathogenesis of LS is probably multifactorial. This review describes several leading etiological factors regarding the potential etiopathogenesis of vulvar LS in girls.

Differentially Regulated miRNAs and Their Related Molecular Pathways in Lichen Sclerosus.

Lichen sclerosus (LS) is a chronic inflammatory skin disorder with unknown pathogenesis. The aberrant expression of microRNAs (miRNAs) is considered to exert a crucial role in LS. We used the next-generation sequencing technology (RNASeq) for miRNA profiling and Ingenuity Pathway Analysis (IPA) for molecular network analysis. We performed qRT-PCR, miRNA transfection and Matrigel assays for functional studies. We identified a total of 170 differentially expressed miRNAs between female LS and matched adjacent normal tissue using RNASeq, with 119 upregulated and 51 downregulated. Bioinformatics analysis revealed molecular networks that may shed light on the pathogenesis of LS. We verified the expression of a set of miRNAs that are related to autoimmunity, such as upregulated miR-326, miR-142-5p, miR-155 and downregulated miR-664a-3p and miR-181a-3p in LS tissue compared to the matched adjacent normal tissue. The differentially expressed miRNAs were also verified in blood samples from LS patients compared to healthy female volunteers. Functional studies demonstrated that a forced expression of miR-142-5p in human dermal fibroblast PCS-201-010 cells resulted in decreased cell proliferation and migration. These findings suggest that differentially expressed miRNAs may play an important role in LS pathogenesis; therefore, they could serve as biomarkers for LS management.

Current treatment of lichen sclerosus and stricture.

Lichen sclerosus (LS) is a common cause of urethral stricture disease. The purpose of this article is to review the literature over the past 5years, to describe current treatment of lichen sclerosus as it relates to urethral stricture in men. Literature reviews were performed using PUBMED, with search terms "lichen scleros*" and "urethral stenosis", as well as "lichen scleros*" and "urethral stricture". Relevant articles published within the past 5years were selected for review. A summary of current treatment of lichen sclerosus was prepared and synthesized. For LS affecting genital skin, topical steroids are a mainstay of therapy but in advanced cases, surgery may be required such as circumcision. When LS causes urethral stricture, urethral dilatation is unlikely to be successful long term, and surgery is often required, such as meatoplasty, single- or two-stage urethroplasty, or perineal urethrostomy. Oral mucosal grafting is the graft of choice, and usage of genital skin for flaps or grafts is best avoided due to predilection for recurrence. Biopsy and long-term surveillance of LS are recommended, due to its potential association with squamous cell carcinoma development. Although debate still exists regarding the pathogenesis of LS, it is agreed that LS can pose a treatment challenge to physicians and surgeons. Treatment options for LS range from pharmacological to surgical, depending on severity and location of disease, patient factors, and response of previous treatments.

Lichen sclerosus: the role of oxidative stress in the pathogenesis of the disease and its possible transformation into carcinoma.

Lichen sclerosus (LS) is an autoimmune chronic inflammatory disease usually involving the anogenital skin of both sexes; more rarely LS exclusively involves extragenital areas. As a chronic inflammatory disease, in most cases, LS evolves and progresses causing scleroatrophy of the skin or scars which may cause stenosis in the affected areas. A few LS patients are at risk of developing squamous cell carcinoma in their lifetime, but appropriate long-term treatment diminishes the possibility of a malignant evolution. Oxidative stress (OS) has been proven to play a role not only in the pathogenesis of LS, but also in the development and progression of the disease. OS, by causing DNA damage and lipid peroxidation, contributes directly to the possible malignant transformation of LS. Moreover, the increase in oxidative DNA damage is associated with mutations in tumor suppressor genes. Considering the role that OS plays in LS, therapeutic use of antioxidants appears to be rational and possible, in association with other treatments. Antioxidants would counteract the oxidative DNA damage, which is the most important factor for the progression of LS and its malignant transformation.

Unusual remodeling of the hyalinization band in vulval lichen sclerosus by type V collagen and ECM 1 protein

OBJECTIVES:The vulva is the primary site affected in lichen sclerosus, a chronic dermatosis in women that is histologically characterized by a zone of collagen remodeling in the superior dermis. The normal physiological properties of the vulva depend on the assembly of collagen types I (COLI), III (COLIII) and V (COLV), which form heterotypic fibers, and extracellular matrix protein interactions. COLV regulates the heterotypic fiber diameter, and the preservation of its properties is important for maintaining normal tissue architecture and function. In the current work, we analyzed the expression of COLV and its relationship with COLI, COLIII, elastic fibers and extracellular matrix protein 1 in vulvar biopsies from patients with lichen sclerosus.METHODS:Skin biopsies from 21 patients with lichen sclerosus, classified according to Hewitt histological criteria, were studied and compared to clinically normal vulvar tissue (N=21). Morphology, immunohistochemistry, immunofluorescence, 3D reconstruction and morphometric analysis of COLI, COLIII, COLV deposition, elastic fibers and extracellular matrix 1 expression in a zone of collagen remodeling in the superior dermis were performed.RESULTS:A significant decrease of elastic fibers and extracellular matrix 1 protein was present in the hyalinization zone of lichen sclerosus compared to healthy controls. The non-homogeneous distribution of collagen fibers visualized under immunofluorescence in the hyalinization zone of lichen sclerosus and control skin was confirmed by histomorphometry. Lichen sclerosus dermis shows a significant increase of COLI, COLIII and COLV expression compared to the healthy controls. Significant inverse associations were found between elastic fibers and COLV and between COLV and extracellular matrix 1 expression. A direct association was found between elastic fiber content and extracellular matrix 1 expression. Tridimensional reconstruction of the heterotypic fibers of the lichen sclerosus zone of collagen remodeling confirmed the presence of densely clustered COLV.CONCLUSIONS:Increased deposition of abnormal COLV and its correlation with extracellular matrix 1 and elastic fibers suggest that COLV may be a trigger in the pathogenesis of lichen sclerosus.

Efficacy of Photodynamic Therapy in Vulvar Lichen Sclerosus Treatment Based on Immunohistochemical Analysis of CD34, CD44, Myelin Basic Protein, and Ki67 Antibodies

Lichen sclerosus (LS) is a chronic skin and mucosa inflammatory disease. It affects mainly the female anogenital area especially in postmenopausal period. The main symptoms include pruritus, burning, pain, sometimes urinary problems, or difficulties in defecation. Usually, porcelain-white plaques are seen in the skin and mucosa. The etiology and pathogenesis of LS are still uncertain. There are some research studies on possible genetic predisposition, yet autoimmune, hormonal, or infectious factors are not excluded. The typical treatment of LS is mainly pharmacological, although the alternative treatment method used in LS is photodynamic therapy (PDT), which is noninvasive technique based on selective destruction of lesions. Our study is focused on molecule markers of vascularisation (CD34), nervous cell function (myelin basic protein [MBP]), keratinocyte function (CD44), and proliferation index (Ki67) in cases treated with photodynamic method. A group of 100 patients treated in our department was included in the study. All 100 women had LS on the basis of clinical and histological criteria. All the subjects underwent PDT. In all cases, skin biopsies were taken before and after treatment, and samples were analyzed with CD34, CD44, MBP, and Ki67 antibodies using immunohistochemical staining. The study shows the high efficacy of PDT in LS treatment including beneficial changes to CD34, CD44, and MBP immunostained molecules. The Ki67 proliferation index did not change significantly. A significant increase of CD34 (microvessel density), MBP, and CD44 expression was confirmed in the histological images and in the partial or full remission of clinical objective and subjective symptoms. The PDT is a very effective therapeutic method in LS treatment.

Detection of perforin and granzyme B mRNA expressing cells in lichen sclerosus

Granzyme B and perforin messenger RNA (mRNA) expression has been shown to be a specific in vivo activation marker for cytotoxic cells. The aim of this study was to assess the contribution of cell-mediated cytotoxicity in the pathogenesis of lichen sclerosus. In situ hybridization and immunohistochemistry were performed on serial tissue sections of lesional skin biopsies and normal skin as control. Immunohistochemical staining showed that the cellular infiltrate of diseased skin consisted predominantly of T cells (CD3+) and some B cells (CD20+). Among T cells CD4+ and CD8+ cells were found in about equal numbers. In normal skin samples perforin and granzyme B mRNA expressing cells were only rarely found. In contrast, in biopsies from diseased skin a high percentage of infiltrating cells expressed mRNA for perforin and granzyme B. The perforin and granzyme B expressing cells were found in the dermal infiltrate and intraepidermally in close proximity to keratinocytes suggesting in situ activation of these cells. These findings provide evidence that cell-mediated cytotoxicity plays a significant role in tissue destruction in lichen sclerosus.

IP10/CXCL10 - CXCR3 Interaction: a Potential Self-recruiting Mechanism for Cytotoxic Lymphocytes in Lichen Sclerosus et Atrophicus

Lichen sclerosus et atrophicus is a chronic inflammatory skin disease of unknown aetiology. Recent studies have indicated that autoimmune mechanisms might be involved in its pathogenesis and have suggested a role for autoreactive cytotoxic T-lymphocytes. Based on recent observations we now hypothesize that a type I interferon-driven inflammation might be involved in the pathogenesis of this disease. Lesional skin biopsies were analysed by immunohistochemistry (CD3, CD4, CD8, CD68, CD123, Tia1, Granzyme B, Myxovirus resistance A, IP10/CXCL10 and CXCR3). Sequential double staining was performed to analyse co-expression of Tia1 and CXCR3. Significant expression of Myxovirus resistance A was found, indicating type I interferon production. This expression was closely associated with the expression of the interferon-inducible protein IP10 and the recruitment of CXCR3+ cytotoxic T-lymphocytes. Plasmacytoid dendritic cells appeared to be a major source of type I interferon in lichen sclerosus et atrophicus. Interestingly, several infiltrating lymphocytes contained IP10 in their granules. This is the first study providing evidence that a type I interferon-associated recruitment of CXCR3+ cytotoxic T-lymphocytes is involved in the pathogenesis of lichen sclerosus et atrophicus. Infiltrating lymphocytes, containing IP10 in their granules, could provide an important self-perpetuating mechanism.

Oxidative stress is implicated in the pathogenesis of lichen sclerosus.

Lichen sclerosus (LS) is a chronic inflammatory skin disease of unknown aetiology which can be associated with secondary malignancies. Recent evidence supports an autoimmune basis for this disorder, as demonstrated by autoantibodies to extracellular matrix protein 1 (ECM-1). The pathophysiological mechanisms leading to autoimmunity and carcinogenesis are poorly understood. We hypothesized that oxidative stress, which has been demonstrated to be involved in the pathogenesis of several autoimmune and malignant disorders, contributes to these processes in LS. Skin biopsies from 16 patients with untreated, histologically confirmed vulval LS were examined immunohistochemically using antibodies against the lipid peroxidation products malondialdehyde and 4-hydroxynonenale and against the oxidative DNA damage marker 8-hydroxy-2'-deoxyguanosine. Protein carbonyls as markers of protein oxidation were visualized using the dinitrophenylhydrazone method. Expression of antioxidant enzymes was investigated. Normal vulval tissue from 16 subjects served as control. In vulval LS tissue a significant increase of lipid peroxidation products was found particularly within the basal cell layers of the epidermis, thus colocalizing with ECM-1. Oxidative DNA damage was detected throughout LS biopsies. Intriguingly, protein oxidation was significantly increased within the dermis of LS lesions, indicating oxidative protein damage in the areas of sclerosis and inflammation. The enzymatic antioxidant defence in LS was found to be significantly disturbed. This is the first study to demonstrate oxidative damage to lipids, DNA and proteins in LS, revealing a novel pathophysiological mechanism which may contribute to sclerosis, autoimmunity and carcinogenesis. Therapeutic strategies using antioxidants might be a useful new approach in the treatment of LS and could also help to prevent secondary malignancies.

Interleukin 1 receptor antagonist gene polymorphism association with lichen sclerosus.

Cytokines play key roles in immune responses, inflammation and fibrosis. The balance between levels of cytokines, their receptors and specific inhibitors controls inflammatory reactions in tissues. The pathogenesis of lichen sclerosus is unknown but probably involves cytokine mediators such as interleukin 1 (IL-1) and interleukin 1 receptor antagonist (IL-1ra). The IL-1ra is a competitive inhibitor of IL-1 alpha and IL-1 beta, and therefore is a powerful endogenous anti-inflammatory molecule. The gene encoding IL-1ra (designated IL-1RN) has a variable number tandem repeat polymorphism in intron 2. There are five alleles of the gene corresponding to 2, 3, 4, 5 and 6 repeats of an 86-bp sequence. We have determined allele frequencies in a control population and a group of 78 patients with lichen sclerosus. The frequency of one of the alleles is related to increasing disease severity. Thus, IL-1RN may be a candidate gene or severity factor for lichen sclerosus or may possibly be a linked marker to another, as yet undefined, gene.

Lichen sclerosus et atrophicus and autoimmunity in 250 women

Whilst the aetiology and pathogenesis of lichen sclerosus et atrophicus (LSA) remain unknown, it has been established that patients with LSA have an increased incidence of autoantibodies (Goolamali et al., 1974) and autoimmune related disorders (Harrington & Dunsmore, 1981; Meyrick Thomas, Ridley & Black, 1983, 1984). As only a proportion of patients with LSA exhibit such a tendency to autoimmune related phenomena, we have sought to determine whether there are any differences in the natural history of LSA in patients having autoantibodies or autoimmune related diseases (personally or in a first degreee relative) compared with those without such features. We have studied 250 women with histologically confirmed LSA. Fifty-two (208%) had a personal history of one or more autoimmune related diseases (vitiligo, alopecia areata, pernicious anaemia, insulin-dependent diabetes mellitus, thyroid disease, bullous pemphigoid); 55 (22%) gave a family history of such autoimmune related disorders; and 109 (436%) had one or more autoantibody in a titre 1:20 or greater. There was a slightly different distribution of age at onset of LSA in the group of patients with an autoimmune related disorder compared with the patients with no associated conditions, but no significant differences were found between those patients with, and those without, autoimmune related phenomena with regard to duration of LSA, onset of LSA in relation to puberty or menopause, site(s) of involvement with LSA and malignant change in LSA-involved skin. We conclude that the tendency to develop autoimmune related phenomena does not reflect a difference in the natural history of LSA in such patients.

Investigation of intercellular matrix macromolecules involved in lichen sclerosus

Dermal changes of the vulva in lichen sclerosus were compared with control vulvar samples using ultrastructural and immunofluorescence techniques. Collagen degeneration and regeneration were observed ultrastructurally in the superficial dermis of lichen sclerosus with increased amounts of ground substance. These processes appeared to alter the affinity of collagen fibres for the anticollagen antisera types I, III, IV. A decrease in elastin content was observed by electron microscopy. A loss of fibronectin was discovered at the dermo-epidermal junction, which looked normal ultrastructurally. The linear laminin pattern at the dermo-epidermal junction was also altered. These results suggested an enzymatic process in the pathogenesis of lichen sclerosus. Amidase activity could be determined in 6 normal and 6 pathological biopsies, though higher in the pathological samples (p less than 0.01).