Genome-wide association study in frontal fibrosing alopecia identifies four susceptibility loci including HLA-B*07:02

Dutasteride in the treatment of frontal fibrosing alopecia: Systematic review and meta-analysis

Frontal fibrosing alopecia (FFA) is a scarring alopecia with fronto-temporo-parietal hairline recession. Although no proven treatment for FFA exists, dutasteride has been suggested as a potential treatment option. We aimed to evaluate the therapeutic response of oral dutasteride in FFA patients. The identification and selection of studies were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis 2020 criteria. To assess the risk of bias for each study, we used the Cochrane's risk of bias in non-randomized studies of interventions (ROBINS-I) assessment tool. A random effects model meta-analysis was performed. Estimated proportion of stabilization for eligible studies was calculated to evaluate the effectiveness of dutasteride for treating FFA. Among patients who achieved stabilization, subgroup analysis was conducted on those showing improvement. Seven studies including 366 patients who received oral dutasteride were identified. The estimated proportion of patients who experienced stabilization of FFA with oral dutasteride was 0.628 (95% CI: 0.398-0.859). In subgroup analyses of patients who experienced improvement, the estimated proportion of improvement was 0.356 (95% CI: 0.163-0.549). In this systematic review and meta-analysis, oral dutasteride revealed to be a good treatment option for disease stabilization or improvement in patients with FFA.

Isotretinoin as a promising option in the treatment of facial papules of frontal fibrosing alopecia

Frontal fibrosing alopecia (FFA) is a primary cicatricial alopecia characterized by hairline recession, pruritus, and facial papules (FP). Various therapies are used to stabilize disease activity and induce remission. However, FP of FFA is resistant to treatment in many cases. In this review, we searched the PubMed and Google Scholar databases to screen the published literature on treatment options for FP in the context of FFA. Overall, 12 studies were included in this review. Available literature suggests a noticeable improvement in resistant-to-treatment FP in FFA patients with oral isotretinoin. The available evidence is limited and is derived from retrospective studies and case reports/series. Systemic isotretinoin can be considered a promising therapeutic regimen for treating resistant-to-treatment FP of FFA patients. However, more extensive, well-designed studies are necessary for confirmatory evidence.

Gene-Environment Interaction Between CYP1B1 and Oral Contraception on Frontal Fibrosing Alopecia

Importance

Frontal fibrosing alopecia (FFA) is an increasingly prevalent form of follicular lichen planus, causing irreversible hair loss predominantly in postmenopausal individuals. An earlier genome-wide meta-analysis of female FFA identified risk loci in genes implicated in self-antigen presentation and T-cell homeostasis, including HLA-B*07:02, ST3GAL1, and SEMA4B. However, CYP1B1, which is important for hormone metabolism, was also implicated with the substitution of serine for asparagine at position 453 (c.1358A>G, p.Asn453Ser) exhibiting a protective effect against FFA. Increasing understanding of genetic and environmental variables and their interactions will improve understanding of disease pathogenesis and has the potential to inform risk mitigation strategies.

Objective

To investigate whether oral contraceptive pill (OCP) use modulates the protective effect of the common missense variant in CYP1B1 (c.1358A>G, p.Asn453Ser) on FFA risk.

Design, Setting, and Participants

This gene-environment interaction study using a case-control design enrolled female patients with FFA from UK-based dermatology clinics. The patients were matched with unrelated age- and ancestry-matched female control individuals derived from UK Biobank in a 1:66 ratio, determined by the first 4 principal components from genome-wide genotypes. Data were collected from July 2015 to September 2017, and analyzed from October 2022 to December 2023.

Main Outcome and Measure

The main outcomes were the modulatory effect of OCP use on the contribution of the CYP1B1 missense variant to female FFA risk and a formal gene-environment interaction test evaluated by a logistic regression model with a multiplicative interaction term, under the assumptions of an additive genetic model interaction term, under the assumptions of an additive genetic model.

Results

Of the 489 female patients with FFA, the mean (SD) age was 65.8 (9.7) years, and 370 (75.7%) had a history of OCP use. Of the 34 254 age- and ancestry-matched control individuals, the mean (SD) age was 65.0 (8.4) years, and previous OCP use was reported in 31 177 (91.0%). An association between female FFA and the CYP1B1 risk allele was observed in individuals who reported OCP use (odds ratio, 1.90 [95% CI, 1.50-2.40]; P = 8.41 × 10-8) but not in those with no documented exposure to OCPs (odds ratio, 1.16 [95% CI, 0.82-1.64]; P = .39). A full gene-environment interaction model demonstrated a significant additive statistical interaction between c.1358A, p.453Asn, and history of OCP use on FFA risk (OR for interaction, 1.63 [95% CI, 1.07-2.46]; P = .02).

Conclusions and Relevance

This gene-environment interaction analysis suggests that the protective effect of the CYP1B1 missense variant on FFA risk might be mediated by exposure to OCPs. The allele that encodes an asparagine at position 453 of CYP1B1 was associated with increased odds of FFA only in participants with OCP history.

Enhanced Insights into Frontal Fibrosing Alopecia: Advancements in Pathogenesis Understanding and Management Strategies

Frontal fibrosing alopecia (FFA) represents a distinctive form of primary lymphocytic scarring alopecia characterized by fronto-temporal hair recession and eyebrow hair loss. While predominantly affecting postmenopausal women, FFA also occurs in women of reproductive age and men, with variations observed across different ethnic groups. Genetic predisposition, environmental factors and inflammatory pathways contribute to its pathogenesis, with evolving diagnostic criteria enhancing accuracy. FFA treatment lacks standardization, encompassing topical, systemic and physical therapies, while hair transplantation remains a temporary solution. This article reviews the current understanding of FFA, aiming to provide clinicians with updated insights for its management.

Navigating Diagnostic Uncertainty: Frontal Fibrosing Alopecia Versus Keratosis Pilaris Atrophicans Faciei With Genetic Testing Insights

Keratosis pilaris atrophicans faciei (KPAF) and frontal fibrosing alopecia (FFA) present diagnostic challenges due to their similar clinical characteristics. Dermatologists often employ overlapping treatment regimens, which may hinder accurate diagnosis and treatment expectations. Genetic testing offers promise for precise diagnosis and tailored treatment strategies, yet its utility in these conditions remains underexplored. This manuscript presents a unique case study of a 36-year-old male with symptoms of both KPAF and FFA, who underwent genetic testing. Despite testing negative for this mutation, the case underscores the potential of genetic testing to enhance diagnostic accuracy and optimize treatment outcomes.

Human Leukocyte Antigen Signatures as Pathophysiological Discriminants of Microscopic Colitis Subtypes

BACKGROUND AND AIMS

Microscopic colitis [MC] is currently regarded as an inflammatory bowel disease that manifests as two subtypes: collagenous colitis [CC] and lymphocytic colitis [LC]. Whether these represent a clinical continuum or distinct entities is, however, an open question. Genetic investigations may contribute important insight into their respective pathophysiologies.

METHODS

We conducted a genome-wide association study [GWAS] meta-analysis in 1498 CC, 373 LC patients, and 13 487 controls from Europe and the USA, combined with publicly available MC GWAS data from UK Biobank and FinnGen [2599 MC cases and 552 343 controls in total]. Human leukocyte antigen [HLA] alleles and polymorphic residues were imputed and tested for association, including conditional analyses for the identification of key causative variants and residues. Genetic correlations with other traits and diagnoses were also studied.

RESULTS

We detected strong HLA association with CC, and conditional analyses highlighted the DRB1*03:01 allele and its residues Y26, N77, and R74 as key to this association (best p = 1.4 × 10-23, odds ratio [OR] = 1.96). Nominally significant genetic correlations were detected between CC and pneumonia [rg = 0.77; p = 0.048] and oesophageal diseases [rg = 0.45, p = 0.023]. An additional locus was identified in MC GWAS analyses near the CLEC16A and RMI2 genes on chromosome 16 [rs35099084, p = 2.0 × 10-8, OR = 1.31]. No significant association was detected for LC.

CONCLUSION

Our results suggest CC and LC have distinct pathophysiological underpinnings, characterised by an HLA predisposing role only in CC. This challenges existing classifications, eventually calling for a re-evaluation of the utility of MC umbrella definitions.

Transcriptome analysis of frontal fibrosis alopecia revealed involvement of immune cells and ferroptosis

BACKGROUND

Frontal fibrosis alopecia (FFA) is a primary cicatricial alopecia and has received increasing attention in recent years. However, the pathogenesis of FFA has not been fully elucidated.

METHODS AND RESULTS

Herein, we collected the transcriptome data of scalp lesions of seven patients with FFA and seven healthy controls. The differential expression analysis and weighted gene co-expression network analysis were conducted and we identified 458 differentially expressed genes (DEGs) in two key modules. Later, we performed functional enrichment analysis and functional modules identification, revealing the participation of immune response and fatty acid metabolism. Based on the results, we processed further studies. On the one hand, we analyzed the infiltrating immune cells of FFA through CIBERSORT algorithm, indicating the activation of M1 macrophage and CD8+ T cell. On the other hand, considering lipid metabolism of FFA and oxidative stress of hair follicle cells in alopecia, we explored the potential ferroptosis of FFA. By intersection of DEGs and ferroptosis-related genes from FerrDb database, 19 genes were identified and their expression was validated in an external dataset containing 36 FFA cases and 12 controls. Then, we used LASSO algorithms to construct a four-gene diagnostic model, which achieved an AUC of 0.924 in validation dataset. Additionally, the immune cells were found to be related to ferroptosis in FFA.

CONCLUSION

Taken together, this study contributed to reveal the molecular mechanisms of FFA and is expected to inspire future research on treatment.

Frontal Fibrosing Alopecia and Reproductive Health: Assessing the Role of Sex Hormones in Disease Development

Frontal Fibrosing Alopecia (FFA) is a distinctive form of cicatricial alopecia characterized by gradual hairline recession, predominantly affecting postmenopausal individuals, thus implying a potential hormonal origin. This narrative review, spanning 2000 to 2023, delves into PubMed literature, focusing on the menopausal and hormonal status of women with FFA. The objective is to unravel the intricate nature of FFA and its plausible associations with hormonal dysregulations in women. While menopause remains a pivotal demographic characteristic linked to FFA, existing data suggest that its hormonal imbalances may not fully account for the development of FFA. Conversely, substantial evidence indicates a strong association between a reduction in fertile years, particularly through surgical interventions leading to an abrupt hormonal imbalance, and FFA in women. Additionally, exposure to hormone replacement therapy or oral contraceptives has shown varying degrees of association with FFA. Gynecologists should maintain a heightened awareness regarding the ramifications of their interventions and their pivotal role in overseeing women's fertility, recognizing the potential influence on the progression of FFA. The recurrent theme of hormonal disruption strongly implies a causal connection between alterations in sex hormones and FFA in women. Nevertheless, this relationship's extent and underlying mechanisms remain subjects of ongoing debate.

Genotyping of the rs1800440 Polymorphism in CYP1B1 Gene and the rs9258883 Polymorphism in HLA-B Gene in a Spanish Cohort of 223 Patients with Frontal Fibrosing Alopecia

The pathogenesis of frontal fibrosing alopecia has been linked to specific genetic variants. CYP1B1 codes for a component of the cytochrome p450 machinery that is involved in the metabolism of xenobiotic oestrogens. The study of the prevalence of polymorphisms in this gene may help to understand their role in the development of frontal fibrosing alopecia. The aim of this study is to describe the frequency of genetic variations in the alleles HLA-B*07:02 and CYP1B1 in patients with frontal fibrosing alopecia. A cross-sectional study was designed to evaluate blood samples from patients with frontal fibrosing alopecia who attended the Dermatology Department at University Hospital Ramón y Cajal (Madrid, Spain), in search of the polymorphisms rs9258883 and rs1800440 in the alleles HLA-B*07:02 and CYP1B1, respectively. A total of 223 patients were included in the study. Among the 83.8% of patients who carried the rs9258883 polymorphism in HLA-B*07:02, 58.7% were heterozygous for this variant and it was not present in 14.8% of the cases. The majority of patients with frontal fibrosing alopecia lacked the protective rs1800440 polymorphism in CYP1B1 (75.2%). This suggests a relevant role of this variant in development of frontal fibrosing alopecia. The genetic approach to this condition might influence patient prognosis and therapy options.

Treatment modalities for lymphocytic and neutrophilic scarring alopecia

Primary cicatricial alopecia can result in permanent hair loss from the destruction of hair follicles. Early intervention is key in controlling disease progression, reducing symptoms, and optimizing hair density. Treatment modalities range from topical and intralesional therapies to oral medications and light therapy.

Recent Advances in Understanding of the Etiopathogenesis, Diagnosis, and Management of Hair Loss Diseases

Hair-loss diseases comprise heterogenous conditions with respective pathophysiology and clinicopathological characteristics. Major breakthroughs in hair follicle biology and immunology have led to the elucidation of etiopathogenesis of non-scarring alopecia (e.g., alopecia areata, AA) and cicatricial alopecia (e.g., lichen planopilaris, LPP). High-throughput genetic analyses revealed molecular mechanism underlying the disease susceptibility of hair loss conditions, such as androgenetic alopecia (AGA) and female pattern hair loss (FPHL). Hair loss attracted public interest during the COVID-19 pandemic. The knowledge of hair loss diseases is robustly expanding and thus requires timely updates. In this review, the diagnostic and measurement methodologies applied to hair loss diseases are updated. Of note, novel criteria and classification/scoring systems published in the last decade are reviewed, highlighting their advantages over conventional ones. Emerging diagnostic techniques are itemized with clinical pearls enabling efficient utilization. Recent advances in understanding the etiopathogenesis and management for representative hair diseases, namely AGA, FPHL, AA, and major primary cicatricial alopecia, including LPP, are comprehensively summarized, focusing on causative factors, genetic predisposition, new disease entity, and novel therapeutic options. Lastly, the association between COVID-19 and hair loss is discussed to delineate telogen effluvium as the predominating pathomechanism accounting for this sequela.

Protein profiling of forehead epidermal corneocytes distinguishes frontal fibrosing from androgenetic alopecia

Protein profiling offers an effective approach to characterizing how far epidermis departs from normal in disease states. The present pilot investigation tested the hypothesis that protein expression in epidermal corneocytes is perturbed in the forehead of subjects exhibiting frontal fibrosing alopecia. To this end, samples were collected by tape stripping from subjects diagnosed with this condition and compared to those from asymptomatic control subjects and from those exhibiting androgenetic alopecia. Unlike the latter, which exhibited only 3 proteins significantly different from controls in expression level, forehead samples from frontal fibrosing alopecia subjects displayed 72 proteins significantly different from controls, nearly two-thirds having lower expression. The results demonstrate frontal fibrosing alopecia exhibits altered corneocyte protein expression in epidermis beyond the scalp, indicative of a systemic condition. They also provide a basis for quantitative measures of departure from normal by assaying forehead epidermis, useful in monitoring response to treatment while avoiding invasive biopsy.

Actinic lichen planopilaris: a new variant of lichen planopilaris triggered by ultraviolet radiation

We present the case of a Sri Lankan woman with a novel clinical entity, actinic lichen planopilaris. Treatment with high-potency topical corticosteroids and adherence to strict photoprotection was successful in treating the disorder.

Frontal fibrosing alopecia: A review of disease pathogenesis

Frontal fibrosing alopecia (FFA) is a primary patterned cicatricial alopecia that mostly affects postmenopausal women and causes frontotemporal hairline regression and eyebrow loss. Although the incidence of FFA has increased worldwide over the last decade, its etiology and pathology are still unclear. We cover the latest findings on its pathophysiology, including immunomodulation, neurogenic inflammation, and genetic regulation, to provide more alternatives for current clinical treatment. A persistent inflammatory response and immune privilege (IP) collapse develop and lead to epithelial hair follicle stem cells (eHFSCs) destruction and epithelial-mesenchymal transition (EMT) in the bulge area, which is the key process in FFA pathogenesis. Eventually, fibrous tissue replaces normal epithelial tissue and fills the entire hair follicle (HF). In addition, some familial reports and genome-wide association studies suggest a genetic susceptibility or epigenetic mechanism for the onset of FFA. The incidence of FFA increases sharply in postmenopausal women, and many FFA patients also suffer from female pattern hair loss in clinical observation, which suggests a potential association between FFA and steroid hormones. Sun exposure and topical allergens may also be triggers of FFA, but this conjecture has not been proven. More evidence and cohort studies are needed to help us understand the pathogenesis of this disease.

Primary cicatricial alopecias are characterized by dysregulation of shared gene expression pathways

The primary forms of cicatricial (scarring) alopecia (PCA) are a group of inflammatory, irreversible hair loss disorders characterized by immune cell infiltrates targeting hair follicles (HFs). Lichen planopilaris (LPP), frontal fibrosing alopecia (FFA), and centrifugal cicatricial alopecia (CCCA) are among the main subtypes of PCAs. The pathogenesis of the different types of PCAs are poorly understood, and current treatment regimens yield inconsistent and unsatisfactory results. We performed high-throughput RNA-sequencing on scalp biopsies of a large cohort PCA patients to develop gene expression-based signatures, trained into machine-learning-based predictive models and pathways associated with dysregulated gene expression. We performed morphological and cytokine analysis to define the immune cell populations found in PCA subtypes. We identified a common PCA gene signature that was shared between LPP, FFA, and CCCA, which revealed a significant over-representation of mast cell (MC) genes, as well as downregulation of cholesterogenic pathways and upregulation of fibrosis and immune signaling genes. Immunohistological analyses revealed an increased presence of MCs in PCAs lesions. Our gene expression analyses revealed common pathways associated with PCAs, with a strong association with MCs. The indistinguishable differences in gene expression profiles and immune cell signatures between LPP, FFA, and CCCA suggest that similar treatment regimens may be effective in treating these irreversible forms of hair loss.

Frontiers in Lichen Planopilaris and Frontal Fibrosing Alopecia Research: Pathobiology Progress and Translational Horizons

Lichen planopilaris (LPP) and frontal fibrosing alopecia (FFA) are primary, lymphocytic cicatricial hair loss disorders. These model epithelial stem cell (SC) diseases are thought to result from a CD8⁺ T-cell‒dominated immune attack on the hair follicle (HF) SC niche (bulge) after the latter has lost its immune privilege (IP) for as yet unknown reasons. This induces both apoptosis and pathological epithelial‒mesenchymal transition in epithelial SCs, thus depletes the bulge, causes fibrosis, and ultimately abrogates the HFs' capacity to regenerate. In this paper, we synthesize recent progress in LPP and FFA pathobiology research, integrate our limited current understanding of the roles that genetic, hormonal, environmental, and other factors may play, and define major open questions. We propose that LPP and FFA share a common initial pathobiology, which then bifurcates into two distinct clinical phenotypes, with macrophages possibly playing a key role in phenotype determination. As particularly promising translational research avenues toward direly needed progress in the management of these disfiguring, deeply distressful cicatricial alopecia variants, we advocate to focus on the development of bulge IP and epithelial SC protectants such as, for example, topically effective, HF‒penetrating and immunoinhibitory preparations that contain tacrolimus, peroxisome proliferator-activated receptor-γ, and/or CB1 agonists.

[Frontal fibrosing alopecia-update]

The number of patients presenting with frontal fibrosing alopecia (FAA) is increasing not only in hair clinics. The recognition of the peculiar clinical pattern and associated symptoms is an important prerequisite to ensure adequate counseling and therapeutic management of the patients. Experimental studies and a range of case series give first insights into the pathogenesis, possible trigger factors, clinical course of disease and treatment options. The clinical spectrum of FFA extends beyond the typical recession of the frontal hair line initially observed in postmenopausal women. Younger women, men and rarely adolescents may also be affected. Band-like extension to the occiput, diffuse bitemporal hair thinning, eyebrow and body hair involvement as well as facial papules are part of the clinical spectrum. Similar to lichen planopilaris, inflammation and fibrosis with involvement of the stem cell region result in permanent loss of hair follicles. Which additional factors contribute to the characteristic pattern remains to be elucidated. Currently, therapeutic management largely relies on anti-inflammatory treatment with combined topical, intralesional and systemic administration depending on disease activity. The chronic progressive course, sometimes even in the absence of pronounced inflammation remains a challenge for both the affected individuals and the treating physicians. Controlled studies are required to develop evidence-based recommendations and to explore novel treatment strategies.

The Association of Frontal Alopecia with a History of Facial and Scalp Surgical Procedures

INTRODUCTION

The prevalence of frontal fibrosing alopecia (FFA) is increasing worldwide, though the pathogenesis remains unknown. Anecdotal reports describe alopecia occurring in an FFA pattern following facial surgical procedures, but this potential link remains unexplored.

OBJECTIVE

The objective of this study is to determine if a significant association exists between the diagnosis of FFA and a history of facial and scalp surgical procedures.

METHODS

This retrospective study comparing data from frontal alopecia patients to controls was conducted at a tertiary medical center. Additionally, a literature review was conducted on scarring alopecias occurring from scalp procedures.

RESULTS

Fifty percent of frontal alopecia patients (n = 54) reported a history of facial surgical procedures compared to 9.8% of controls (n = 51) (OR: 7.8 [95% CI: 2.77-25.98, p < 0.001]). Although no significant differences were observed in current daily facial sunscreen use, sunscreen use prior to alopecia onset was significantly higher in frontal alopecia (p = 0.295; p = 0.021). Sunscreen use was not a significant modifier in the association between frontal alopecia and facial surgical procedures (p = 0.89).

CONCLUSIONS

A significant association exists between frontal alopecia clinically consistent with FFA and a history of facial surgery, the nature of which is unclear. The role of sunscreen use and frontal alopecia development in this setting needs to be better elucidated.

Frontal Fibrosing Alopecia survey of severity assessment methods in routine clinical practice and validation of the IFFACG measurement guidance

BACKGROUND

Lack of validated and responsive outcome measures in the management of Frontal Fibrosing Alopecia (FFA) significantly limits our ability to assess disease progression and treatment response over time.

OBJECTIVES

The aim of this study was to understand how FFA extent and progression is currently assessed in UK specialist centres, validate components of the International FFA Cooperative Group (IFFACG) statement on FFA assessment, and identify pragmatic advice to improve FFA management in clinic.

METHODS

Consultant Dermatologists with a specialist interest in hair loss (n=17) were invited to take part. Preferred FFA assessment methods were explored using questionnaires and clinical scenarios. Participants were asked to identify and mark the current hairline in 10 frontal and 10 temporal hairline images, with assessment repeated 3 months later (to assess intra-individual variability) and 12 months later (to test whether inter-individual accuracy could be improved with simple instruction).

RESULTS

All 17 clinicians (100%) completed the questionnaire at each time interval. We identified a wide variation in assessment techniques between our experts. Measurements were perceived as the most accurate method of assessing frontal recession whereas photography was preferred for temporal recession. Inter-rater reliability between clinicians measuring the frontal hairline scenarios indicated a moderate strength of agreement (ICC 0.613; 95% CI: 0.398 to 0.848), yet intra-rater reliability was found to be poor with wide limits of agreement (-8.71mm to 9.92mm) on follow-up. Importantly, when clear guidance was provided on how the hairline should be identified (questionnaire 3), inter-rater reliability improved significantly, with an ICC 0.702 suggesting moderate agreement (95% CI: 0.508 to 0.890; p<0.001). A similar pattern was seen with temporal hairline measurements, which again improved in accuracy with instruction.

CONCLUSION

We show that accuracy of measurements in FFA can be improved with simple instruction and validate components of the IFFACG measurement recommendations.

Scarring Alopecias: Pathology and an Update on Digital Developments

Primary cicatricial alopecias (PCA) represent a challenging group of disorders that result in irreversible hair loss from the destruction and fibrosis of hair follicles. Scalp skin biopsies are considered essential in investigating these conditions. Unfortunately, the recognised complexity of histopathologic interpretation is compounded by inadequate sampling and inappropriate laboratory processing. By sharing our successes in developing the communication pathway between the clinician, laboratory and histopathologist, we hope to mitigate some of the difficulties that can arise in managing these conditions. We provide insight from clinical and pathology practice into how diagnoses are derived and the key histological features observed across the most common PCAs seen in practice. Additionally, we highlight the opportunities that have emerged with advances in digital pathology and how these technologies may be used to develop clinicopathological relationships, improve working practices, enhance remote learning, reduce inefficiencies, optimise diagnostic yield, and harness the potential of artificial intelligence (AI).

Active Exsolved Metal-Oxide Interfaces in Porous Single-Crystalline Ceria Monoliths for Efficient and Durable CH4 /CO2 Reforming

Dry reforming of CH₄ /CO₂ provides an attractive route to convert greenhouse gas into syngas; however, the resistance to sintering and coking of catalyst remains a fundamental challenge at high operation temperatures. Here we create active and durable metal-oxide interfaces in porous single-crystalline (PSC) CeO₂ monoliths with in situ exsolved single-crystalline (SC) Ni particles and show efficient dry reforming of CH₄ /CO₂ at temperatures as low as 450 °C. We show the excellent and durable performance with ≈20 % of CH₄ conversion and ≈30 % of CO₂ conversion even in a continuous operation of 240 hours. The well-defined active metal-oxide interfaces, created by exsolving SC Ni nanoparticles from PSC Ni_x Ce_1-x O₂ to anchor them on PSC CeO₂ scaffolds, prevent nanoparticle sintering and enhance the coking resistance due to the stronger metal-support interactions. Our work would enable an industrially and economically viable path for carbon reclamation, and the technique of creating active and durable metal-oxide interfaces in PSC monoliths could lead to stable catalyst designs for many challenging reactions.

Differentiation of frontal fibrosing alopecia and Lichen planopilaris on trichoscopy: A comprehensive review

Trichoscopy in dermatology has opened up the new concept in overcoming the optical challenge faced clinically. It reveals the diagnostic details to the depth of superficial dermis, and thereby increasing the clinician's diagnostic accuracy and the level of confidence. The importance of trichoscopy in cicatricial alopecia is very evident in the current scenario for its precise diagnosis. The clinical picture in delineating lichen planopilaris (LPP) and frontal fibrosing alopecia (FFA) from each other and also from other close mimickers such as androgenetic alopecia, alopecia areata, female patterned hair loss, and other cicatricial alopecia is bewildered due to its varied presentation and co-existence with the above disease. The indecisive comparative findings on histopathology make the situation even more perplexed. In this article, we have reviewed the characteristic trichoscopy patterns that can differentiate LPP and FFA and from their close mimickers.

Distinctive age distribution and hair loss pattern putatively highlighting uniqueness of Japanese cases of fibrosing alopecia in a pattern distribution

Fibrosing alopecia in a pattern distribution (FAPD) is a unique entity which presents clinicopathological characteristics of both male/female pattern androgenetic alopecia (AGA) and lichen planopilaris (LPP). This entity was first reported in 2000 and its criteria was recently proposed. Etiopathogenesis of FAPD has been speculated to be immunological destruction involving miniaturized hair follicles but still remains elusive. To date, few Asian FAPD cases have been reported in the literature. In this study, Japanese FAPD cases were identified based on the aforementioned criteria and analyzed to delineate clinicopathological characteristics. By retrospectively revisiting medical records and clinical photographs, 24 Japanese cases comprising 17 women and seven men were diagnosed as FAPD. All male patients had disease onset by their early 30s, whereas most female patients had developed the condition in middle age or later. Their initial diagnoses prior to the diagnostic confirmation of FAPD were mostly LPP. Based on the clinical phenotypes, the cases were categorized into AGA and LPP types. These subtypes were characterized by foremost trichoscopic and histopathological findings of AGA or LPP, respectively. Unlike previously reported cases, our patients tended to manifest hair loss in both vertex and frontal to mid-scalp with minimal regression of anterior hairline, manifesting unique "parachute" pattern, which has been reported as a representative characteristic of East Asian AGA in the literature. Anti-inflammatory therapies seemed to be effective to deter hair loss but insufficient to achieve improvement. Further accumulation of the cases is necessary; however, these findings may provide additional pathophysiological insights into FAPD and highlight uniqueness of the etiology and clinical phenotype of Japanese FAPD putatively influenced by racial predispositions.

Fine Mapping of the MHC Region Identifies Novel Variants Associated with HBV-Related Hepatocellular Carcinoma in Han Chinese

Introduction

Genome-wide association studies identified susceptibility loci in the major histocompatibility complex region for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). However, the causal variants underlying HBV-related HCC pathogenesis remain elusive.

Methods

With a total of 1,161 HBV-related HCC cases and 1,353 chronic HBV carriers without HCC, we imputed human leukocyte antigen (HLA) variants based on a Chinese HLA reference panel and evaluated the associations of these variants with the risk of HBV-related HCC. Conditional analyses were used to identify independent signals associated with the risk of HBV-related HCC (P false-discovery rate (FDR) <0.20). A total of 14,930 variants within the MHC region were genotyped or imputed.

Results

We identified two variants, rs114401688 (P = 1.05 × 10⁻⁶, P_FDR = 2.43 × 10⁻³) and rs115126566 (P = 9.04 × 10⁻⁵, P_FDR = 1.77 × 10⁻¹), that are independently associated with the risk of HBV-related HCC. Single nucleotide polymorphism (SNP) rs114401688 is in linkage disequilibrium with a previously reported SNP rs9275319. In the current study, we found that its association with HCC could be explained by HLA-DQB1*04 and HLA-DRB1*04. SNP rs115126566 is a novel risk variant and may function by regulating transcriptions of HLA-DPA1/DPB1 through enhancer-mediated mechanisms. HLA zygosity analysis showed that homozygosity at HLA-DQB1 gene is suggestively associated with a higher risk of HCC (P = 0.10) and the risk was more pronounced in the older age group (age ≥50, P = 0.03).

Discussion

Our findings further the understanding of the genetic basis for HBV-related HCC predisposition in chronic HBV carriers.

Use of facial care products and frontal fibrosing alopecia: Coincidence or true association?

The increasing incidence of frontal fibrosing alopecia (FFA) suggests that environmental factors may be related to the pathogenesis. Recent studies reported potential association between the use of facial care products and FFA. The aim of this study was to investigate the possible association between the use of facial care products and FFA in Asian females. A total of 250 females (50 FFA patients, 100 pattern hair loss [PHL] patients, and 100 normal controls) were recruited and completed a questionnaire to obtain information approximately facial care products and various environmental factors. Our study revealed the use of moisturizer to be significantly higher in the FFA group compared to normal controls (p < 0.001), and sunscreen use was significantly higher in the PHL group than in the control group (adjusted p < 0.001). Subjects with FFA or PHL reported significantly higher use of both sunscreen and moisturizer compared to normal controls (p < 0.001). This study focused on Asian populations. Our results revealed a high frequency of moisturizer and sunscreen use in both FFA and PHL among Asian females. Therefore, the use of facial care products appears not to be linked to the true disease mechanism of FFA, but rather to appearance-related concerns of patients.

Scarring Alopecia: Diagnosis and New Treatment Options

This article focuses on the assessment and treatment of patients with primary cicatricial alopecia and provides new information regarding the genetics and pathophysiology of this group of diseases.

Familial Frontal Fibrosing Alopecia: Report of a case and systematic review of the literature

Frontal fibrosing alopecia (FFA) is an emerging disease in Western countries. We present the cases of three sisters who were referred simultaneously to the Department of Dermatology, Hospital Universitario San Cecilio, Granada, Spain, in 2018. All patients suffered from at least partial frontotemporal hairline recession and eyebrow loss. Following trichoscopic examination, the three sisters were diagnosed with FFA. Only one of the sisters agreed to be treated; she was prescribed with topical clobetasol propionate solution and minoxidil and achieved disease control at the three-month follow-up. These patients represent a new case of familial FFA wherein three sisters as well as their mother were affected by FFA. A systematic review found a total of 24 cases of familial FFA, of which this report is the 25th. In the majority of families, only females were affected (88%) while in the remainder both males and females (8%) were affected; there was only one family where only males were affected (4%). The relationship between the affected individuals was predominately between sisters (56%) followed by mother and daughter (32%). The median age was 61 years old (range: 14–88 years) and the duration of the disease ranged between 3–360 months. Family groups of FFA are an infrequently described phenomenon with unknown prevalence.

Guidelines for clinical trials of frontal fibrosing alopecia: consensus recommendations from the International FFA Cooperative Group (IFFACG)

BACKGROUND

Frontal fibrosing alopecia (FFA) has become one of the most common causes of cicatricial alopecia worldwide. However, there is a lack of clear aetiology and robust clinical trial evidence for the efficacy and safety of agents currently used for treatment.

OBJECTIVES

To enable data to be collected worldwide on FFA using common criteria and assessment methods.

METHODS

A multicentre, international group of experts in hair loss was convened by email to create consensus recommendations for clinical trials. Consensus was defined at > 90% agreement on each recommended part of these guidelines.

RESULTS

Standardized diagnostic criteria, severity rating, staging, and investigator and patient assessment of scalp hair loss and other clinical features of FFA were created.

CONCLUSIONS

These guidelines should allow the collection of reliable aggregate data on FFA and advance efforts in both clinical and basic research to close knowledge gaps in this condition.

Frontal Fibrosing Alopecia: Is There a Link in Relatives?

Frontal fibrosing alopecia (FFA) is an acquired primary lymphocytic cicatricial alopecia characterized by frontotemporal hairline recession, leading to scarring alopecia with a band-like distribution. Prevalence is increasing worldwide, being the most frequent cause of primary scarring alopecia. The natural history of this condition is variable; however, slow progression with spontaneous remission is the most frequent reported outcome. The etiopathogenesis of FFA remains to be elucidated; numerous hypotheses concerning hormonal effects, environmental factors, and genetic predisposition have been proposed. Special interest on genetic basis has emerged since the first familial case was reported. Only a few more familial cases have been published. We report 6 additional cases of female patients with familial FFA (F-FFA) from 3 different families. Sixty-six percent had a family history of autoimmune disease in first-degree relatives; these same patients had a personal history of autoimmune disease. The families described in this cohort study plus the personal and family history of autoimmune disease, as well as the recently described involved genomic loci; reinforced the hypothesis of this disease being genetic. It is important to consider studying this entity since there are scarce data regarding familial cases and this might give us a better insight toward understanding its pathogenesis.

A Cell Membrane-Level Approach to Cicatricial Alopecia Management: Is Caveolin-1 a Viable Therapeutic Target in Frontal Fibrosing Alopecia?

Irreversible destruction of the hair follicle (HF) in primary cicatricial alopecia and its most common variant, frontal fibrosing alopecia (FFA), results from apoptosis and pathological epithelial-mesenchymal transition (EMT) of epithelial HF stem cells (eHFSCs), in conjunction with the collapse of bulge immune privilege (IP) and interferon-gamma-mediated chronic inflammation. The scaffolding protein caveolin-1 (Cav1) is a key component of specialized cell membrane microdomains (caveolae) that regulates multiple signaling events, and even though Cav1 is most prominently expressed in the bulge area of human scalp HFs, it has not been investigated in any cicatricial alopecia context. Interestingly, in mice, Cav1 is involved in the regulation of (1) key HF IP guardians (TGF-β and α-MSH signaling), (2) IP collapse inducers/markers (IFNγ, substance P and MICA), and (3) EMT. Therefore, we hypothesize that Cav1 may be an unrecognized, important player in the pathobiology of cicatricial alopecias, and particularly, in FFA, which is currently considered as the most common type of primary lymphocytic scarring alopecia in the world. We envision that localized therapeutic inhibition of Cav1 in management of FFA (by cholesterol depleting agents, i.e., cyclodextrins/statins), could inhibit and potentially reverse bulge IP collapse and pathological EMT. Moreover, manipulation of HF Cav1 expression/localization would not only be relevant for management of cicatricial alopecia, but FFA could also serve as a model disease for elucidating the role of Cav1 in other stem cell- and/or IP collapse-related pathologies.

Frontal Fibrosing Alopecia: A Review

Frontal fibrosing alopecia is a scarring alopecia, the prevalence of which is increasing worldwide since its first description in 1994. The reason for this emerging epidemic may be a higher exposure to an unknown trigger, although its aethiology and pathogenesis still remain enigmatic. Clinical, trichoscopic, sonographic, and histopathologic findings are allowing clinicians to understand more aspects about this type of cicatricial alopecia. Several treatments have been used in frontal fibrosing alopecia, although the 5-alpha reductase inhibitors seem to be the most promising. The aim of this report is to provide a compilation about the published data regarding frontal fibrosing alopecia in a narrative review.

EigenGWAS: An online visualizing and interactive application for detecting genomic signatures of natural selection

Detecting genetic regions under selection in structured populations is of great importance in ecology, evolutionary biology and breeding programmes. We recently proposed EigenGWAS, an unsupervised genomic scanning approach that is similar to F ST but does not require grouping information of the population, for detection of genomic regions under selection. The original EigenGWAS is designed for the random mating population, and here we extend its use to inbred populations. We also show in theory and simulation that eigenvalues, the previous corrector for genetic drift in EigenGWAS, are overcorrected for genetic drift, and the genomic inflation factor is a better option for this adjustment. Applying the updated algorithm, we introduce the new EigenGWAS online platform with highly efficient core implementation. Our online computational tool accepts plink data in a standard binary format that can be easily converted from the original sequencing data, provides the users with graphical results via the R-Shiny user-friendly interface. We applied the proposed method and tool to various data sets, and biologically interpretable results as well as caveats that may lead to an unsatisfactory outcome are given. The EigenGWAS online platform is available at www.eigengwas.com, and can be localized and scaled up via R (recommended) or docker.

The Potential Relevance of the Microbiome to Hair Physiology and Regeneration: The Emerging Role of Metagenomics

Human skin and hair follicles are recognized sites of microbial colonization. These microbiota help regulate host immune mechanisms via an interplay between microbes and immune cells, influencing homeostasis and inflammation. Bacteria affect immune responses by controlling the local inflammatory milieu, the breakdown of which can result in chronic inflammatory disorders. Follicular microbiome shifts described in some inflammatory cutaneous diseases suggest a link between their development or perpetuation and dysbiosis. Though the hair follicle infundibulum is an area of intense immunological interactions, bulb and bulge regions represent immune-privileged niches. Immune privilege maintenance seems essential for hair growth and regeneration, as collapse and inflammation characterize inflammatory hair disorders like alopecia areata and primary cicatricial alopecia. Current research largely focuses on immunological aberrations. However, studies suggest that external stimuli and interactions across the follicular epithelium can have profound effects on the local immune system, homeostasis, and cycling. Herein, we review hair follicle bacterial colonization, its possible effects on the underlying tissue, and links to the pathogenesis of alopecia, beyond the pure investigation of specific species abundance. As skin microbiology enters the metagenomics era, multi-dimensional approaches will enable a new level of investigations on the effects of microorganisms and metabolism on host tissue.

Colour Doppler ultrasound study in patients with frontal fibrosing alopecia

BACKGROUND

The sonographic characteristics of frontal fibrosing alopecia have been scarcely studied. The aim of this study was to perform a colour Doppler ultrasound evaluation in frontal fibrosing alopecia.

MATERIALS AND METHODS

A cross-sectional study including 99 women with frontal fibrosing alopecia and 40 control subjects was performed using ultrasound equipment with a lineal 18 MHz probe. Three areas were evaluated per patient: the alopecic area (a), the hairline implantation area (b) and healthy scalp (c). The diameter (cm) and flow (m/s) of the two most significant vessels were recorded.

RESULTS

With regard to the hairline implantation area, patients presented higher vessel diameter (0.127 cm vs 0.103 cm, P = .03) and vessel flow (8.183 m/s vs 7.670 m/s, P = .05) than the control group. Vessel diameter was higher in the healthy scalp area in patients than in the control group (0.088 cm vs 0.078 cm, P = .03).

CONCLUSION

Patients presented higher vessel diameter and flow in the hairline implantation area compared to the control group.

Hormonal Contraceptives and Dermatology

Hormones play a significant role in normal skin physiology and many dermatologic conditions. As contraceptives and hormonal therapies continue to advance and increase in popularity, it is important for dermatologists to understand their mechanisms and dermatologic effects given the intricate interplay between hormones and the skin. This article reviews the dermatologic effects, both adverse and beneficial, of combined oral contraceptives (COCs), hormonal intrauterine devices (IUDs), implants, injections, and vaginal rings. Overall, the literature suggests that progesterone-only methods, such as implants and hormonal IUDs, tend to trigger or worsen many conditions, including acne, hirsutism, alopecia, and even rosacea. Therefore, it is worthwhile to obtain detailed medication and contraceptive histories on patients with these conditions. There is sufficient evidence that hormonal contraceptives, particularly COCs and vaginal rings, may effectively treat acne and hirsutism. While there are less data to support the role of hormonal contraceptives in other dermatologic disorders, they demonstrate potential in improving androgenetic alopecia and hidradenitis suppurativa.

Optimal Management of Frontal Fibrosing Alopecia: A Practical Guide

Frontal fibrosing alopecia (FFA) is a primary lymphocytic cicatricial alopecia that is often considered a clinical variant of lichen planopilaris (LPP) due to their shared histopathologic features. FFA is characterized by the recession of the frontal, temporal, or frontotemporal hairline; the clinical pattern is distinct and usually includes eyebrow hair loss, as well as other associated symptoms. Pruritus, facial papules, eyelash loss, body hair involvement, and trichodynia may also occur in addition to the frontotemporal recession and eyebrow loss classically seen. Early diagnosis and prompt treatment are critical as FFA is a progressive disorder that can result in permanent hair loss. FFA is challenging as patients may not present or be recognized until the disease has progressed. Additionally, there is currently no consensus or standard treatment regimen for FFA. While many different therapies have been reported as beneficial, there are a limited number of published guidelines for the treatment of FFA. This article is a review of the literature on treatment modalities for FFA and the objective is to offer a practical guide for clinicians on the evidence-based management options currently available in the literature.

Frontal fibrosing alopecia

Frontal fibrosing alopecia (FFA) is a patterned primary cicatricial alopecia that was first described in 1994. Once rare, the incidence of FFA has increased dramatically, representing the current most common cause of cicatricial alopecia worldwide. FFA typically begins in postmenopausal women with symmetrical, progressive recession of the frontotemporal hairline together with bilateral loss of the eyebrows. FFA has a distinctive clinical phenotype, which remains a challenge. The histology is identical to lichen planopilaris (LPP), but only a small number of patients have coincidental LPP, usually of the scalp. The vast majority of patients have no evidence of lichen planus elsewhere, and the symmetry and patterned nature of the hair loss are unusual for LPP. Familial cases of FFA are reported, and gene associations have been identified in population studies; however, the pathophysiology remains controversial. Without treatment, FFA is slowly progressive, and although many treatments have been prescribed, the response is often disappointing. We review the pathogenesis, epidemiology, clinical features, histology, and treatment of FFA.

Dissemination and analysis of the quality assurance (QA) and quality control (QC) practices of LC-MS based untargeted metabolomics practitioners

INTRODUCTION

The metabolomics quality assurance and quality control consortium (mQACC) evolved from the recognized need for a community-wide consensus on improving and systematizing quality assurance (QA) and quality control (QC) practices for untargeted metabolomics.

OBJECTIVES

In this work, we sought to identify and share the common and divergent QA and QC practices amongst mQACC members and collaborators who use liquid chromatography-mass spectrometry (LC-MS) in untargeted metabolomics.

METHODS

All authors voluntarily participated in this collaborative research project by providing the details of and insights into the QA and QC practices used in their laboratories. This sharing was enabled via a six-page questionnaire composed of over 120 questions and comment fields which was developed as part of this work and has proved the basis for ongoing mQACC outreach.

RESULTS

For QA, many laboratories reported documenting maintenance, calibration and tuning (82%); having established data storage and archival processes (71%); depositing data in public repositories (55%); having standard operating procedures (SOPs) in place for all laboratory processes (68%) and training staff on laboratory processes (55%). For QC, universal practices included using system suitability procedures (100%) and using a robust system of identification (Metabolomics Standards Initiative level 1 identification standards) for at least some of the detected compounds. Most laboratories used QC samples (>86%); used internal standards (91%); used a designated analytical acquisition template with randomized experimental samples (91%); and manually reviewed peak integration following data acquisition (86%). A minority of laboratories included technical replicates of experimental samples in their workflows (36%).

CONCLUSIONS

Although the 23 contributors were researchers with diverse and international backgrounds from academia, industry and government, they are not necessarily representative of the worldwide pool of practitioners due to the recruitment method for participants and its voluntary nature. However, both questionnaire and the findings presented here have already informed and led other data gathering efforts by mQACC at conferences and other outreach activities and will continue to evolve in order to guide discussions for recommendations of best practices within the community and to establish internationally agreed upon reporting standards. We very much welcome further feedback from readers of this article.

RNA sequence analysis of dermal papilla cells' regeneration in 3D culture

It is well known that dermal papilla cells (DPCs) are crucial for hair follicle growth and regeneration. However, dermal papilla cells in 2D culture could lose their ability of regeneration after several passage intervals. As opposed to DPCs in 2D culture, the DPCs in 3D culture could passage extensively. However, the molecular mechanisms of DPCs’ regeneration in 3D culture remain unclear. Accordingly, gene sequencing is recommended for the investigation of hair regeneration between 2D and 3D culture, the three groups were established including DPCs in passage 2 in 2D culture, DPCs in passage 8 in 2D culture and DPCs in passage 8 in 3D culture. The differentially expressed genes (DEGs) were identified using the Venn diagram of these three groups, which included 1642 known and 359 novel genes, respectively. A total of 1642 known genes were used for Gene Ontology (GO), Kyoto Gene, Genomic Encyclopedia (KEGG) pathway enrichment and protein‐protein interaction (PPI) analyses, respectively. The functions and pathways of DEGs were enriched in biological regulation, signal transduction and immune system, etc. The key module and the top 10 hub genes (IL1B, CXCL12, HGF, EGFR, APP, CCL2, PTGS2, MMP9, NGF and SPP1) were also identified using the Cytoscape application. Furthermore, the qRT‐PCR results of the three groups validated that the hub genes were crucial for hair growth. In conclusion, the ten identified hub genes and related pathways in the current study can be used to understand the molecular mechanism of hair growth, and those provided a possibility for hair regeneration.

Risk factors for frontal fibrosing alopecia: A case-control study in a multiracial population

BACKGROUND

Frontal fibrosing alopecia (FFA) is a chronic cicatricial alopecia with unknown etiology and a worldwide rising incidence.

OBJECTIVE

The objective of this study was to evaluate the association of FFA with demographic and exposure factors in a Brazilian multiracial population.

METHODS

A multicenter case-control study was conducted in 11 referral centers throughout Brazil. The study was a case-control study that prospectively recruited 902 participants (451 patients with FFA and 451 sex-matched control individuals). Study participants completed a thorough questionnaire comprising variables grouped as baseline demographics, environmental exposure, diet, hormonal factors, allergies, and hair and skin care.

RESULTS

When adjusted by sex, age, menopause, and skin color, FFA was associated with hair straightening with formalin (odds ratio [OR], 3.18), use of ordinary (nondermatologic) facial soap (OR, 2.09) and facial moisturizer (OR, 1.99), thyroid disorders (OR, 1.69), and rosacea (OR, 2.08). Smokers (OR, 0.33) and users of antiresidue/clarifying shampoo (OR, 0.35) presented a negative association with FFA. There was no association with the use of sunscreen.

LIMITATIONS

Recall bias.

CONCLUSIONS

The association with moisturizers, ordinary facial soap, and hair straightening with formalin and the negative association with antiresidue/clarifying shampoo reinforce the possibility of an exogenous particle triggering FFA.