P48 m6A-RNA methylation in severe epidermolysis bullosa simplex: a pilot study

Abstract Introduction and aims N6-methyladenosine (m6A) RNA modification has been implicated in key cutaneous physiological processes, including differentiation, inflammation, immunity, and wound healing. We sought to explore m6A regulation in the setting of severe epidermolysis bullosa simplex (EBS), a rare inherited keratinopathy biologically characterized by disruption of keratin intermediate filament networks within basal keratinocytes, keratin aggregation, cytolysis and persistent inflammation that compounds impaired keratin cycling. This gives rise to skin fragility and persistent wounds, frequently exerting devastating impacts on quality of life. Despite its established relevance in other dermatoses, the role of m6A in EBS has yet to be explored. Methods We investigated the gene expression of key proteins involved in m6A regulation (writers, readers, and erasers) as well as overall RNA m6A levels in KEB-7 cells (KRT14 R125P) derived from a patient with severe autosomal dominant EBS. NEB-1 cells, derived from a healthy donor, served as controls. Analyses were performed using mRNA sequencing, quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), and RNA m6A colorimetry assay. Results Differential gene expression analysis of KEB-7 cells showed upregulation of the m6A writer METTL14 and readers YTHDC1, YTHDF2, and YTHDF3. Downregulation of the reader YTHDF1 and the eraser FTO was also observed. qRT-PCR validated the significant upregulation of METTL14 and YTHDC1 and downregulation of FTO. Total RNA m6A levels were elevated in KEB-7 cells compared with NEB-1 cells. We hypothesize that m6A dysregulation modulates the phenotype observed in severe EBS. Conclusions This pilot study identifies m6A RNA methylation dysregulation as a potential modifier of genotype–phenotype correlation in severe EBS. These findings align with existing evidence supporting the role of m6A in inflammation and immune regulation. Targeted m6A level regulation using activators or inhibitors of writers, erasers and readers may impact T-cell regulation, promote keratinocyte migration, and attenuate deleterious inflammatory responses with potential to improve wound management and quality of life in EBS.