Abstract
Purpose :
Pterygium is a common ocular surface condition related to irritative and vision symptoms and controversies regarding to its mechanisms, treatment and recurrence rates. Despite the association of the inflammatory changes observed in these patients and its similarity to proliferative conditions, the precise identity of their critical triggers as well as all the elements involved in the pathogenesis of this disease are yet to be described. Meta-analysis of gene expression studies from public repositories represents a novel strategy, capable to identify key pathogenic mediators and therapeutic targets. The recent development of comprehensive bioinformatic tools further facilitated the identification of relevant genes, pathways and regulatory elements from high-throughput transcriptomic data.
Methods :
We performed herein a meta-analysis of recent gene expression studies with pterygium patients, available at the Gene Expression Omnibus public repository. Two databases including samples from adults with pterygium fulfilled our inclusion criteria. Meta-analysis was performed with the Inmex bioinformatics tool. Raw data was downloaded, annotated, preprocessed and submitted to quality check. Differentially expressed genes were identified and ranked based on the RankProd package. Gene set analysis using more than 60 libraries was performed using EnrichR. Transcription factor, kinase enrichment, and pathway cluster analysis were performed using appropriate bioinformatic tools.
Results :
We found that the association between inflammation and pterygium was also consistently observed at the transcriptomic level, across independent gene expression studies. The enrichment of genes and pathways associated with collagen biosynthesis, modifying enzymes, degradation of the extracellular matrix, activation of matrix metalloproteinases and inflammatory response pathway were identified as key mediators in the pathogenesis of pterygium. Additionally, regulation of epithelial cell proliferation, DNA damage response, keratinocyte differentiation and apoptosis modulation were found to be down-regulated in pterygium samples.
Conclusions :
Our study generated a novel and large database of candidate genes, pathways, transcription factors and kinases associated with the pathogenesis of pterygium, that could be used in future and independent studies in pterygium.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.