Epithelial dysplasia in pterygium postoperative granuloma

Increased expression of Filaggrin and Claudin-1 in the ocular surface of patients with atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is an itchy, chronic and inflammatory skin condition, with dysfunctional immune response and skin barrier defects. Reduction of filaggrin (FLG) and tight junctions (TJ) proteins, such as claudin-1 (CLDN-1), expression in cutaneous epithelial barrier is remarkable in AD pathogenesis. Ocular involvement occurs in approximately 40% of AD patients leading to changes in the structure of the conjunctiva.

OBJECTIVES

We aimed to evaluate the expression of FLG and CLDN-1 in the ocular surface of adults with AD, analysing bulbar conjunctival cells collected by a novel non-invasive cellular imprint.

METHODS

Bulbar conjunctival epithelial cells were collected by cellular imprint technique, and FLG and CLDN-1 expression were assessed by immunofluorescence (IF) and real-time polymerase chain reaction (RT-PCR).

RESULTS

We detected increased expression of FLG and CLDN-1, as well as their transcript levels in AD patients compared with healthy controls (HC). There was a positive correlation between tear film break-up time (TBUT) and FLG expression. Fluorescein staining was inversely associated with FLG expression.

CONCLUSIONS

Our results may reflect a reactive response of the ocular surface to AD-related ocular inflammation and associated dry eye disease. Further investigations focusing on the role of FLG and TJ expression in the ocular surface of AD patients may increment the understanding of the pathophysiology of extracutaneous AD and developing future targeted therapies.

Exploring the Molecular Mechanisms of Pterygium by Constructing lncRNA-miRNA-mRNA Regulatory Network

Purpose

This research explores the aberrant expression of the long non-coding RNA (lncRNA), microRNA (miRNA), and messenger RNA (mRNA) in pterygium. A competitive endogenous RNA (ceRNA) network was constructed to elucidate the molecular mechanisms in pterygium.

Methods

We obtained the differentially expressed mRNAs based on three datasets (GSE2513, GSE51995, and GSE83627), and summarized the differentially expressed miRNAs (DEmiRs) and differentially expressed lncRNAs (DELs) data by published literature. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, protein-protein interaction (PPI), and gene set enrichment analysis (GSEA) analysis were performed. DEmiRs were verified in GSE21346, and the regulatory network of hub mRNAs, DELs, and DEmiRs were constructed.

Results

Overall, 40 upregulated and 40 downregulated differentially expressed genes (DEGs) were obtained. The KEGG enrichment showed the DEGs mainly involved in extracellular matrix (ECM)-receptor interaction, focal adhesion, and PI3K-Akt signaling pathway. The GSEA results showed that cornification, keratinization, and cornified envelope were significantly enriched. The validation outcome confirmed six upregulated DEmiRs (miR-766-3p, miR-184, miR-143-3p, miR-138-5p, miR-518b, and miR-1236-3p) and two downregulated DEmiRs (miR-200b-3p and miR-200a-3p). Then, a ceRNA regulatory network was constructed with 22 upregulated and 15 downregulated DEmiRs, 4 downregulated DELs, and 26 upregulated and 33 downregulated DEGs. The network showed that lncRNA SNHG1/miR-766-3p/FOS and some miRNA-mRNA axes were dysregulated in pterygium.

Conclusions

Our study provides a novel perspective on the regulatory mechanism of pterygium, and lncRNA SNHG1/miR-766-3p/FOS may contribute to pterygium development.