Abstract
Purpose :
Cataract development accelerates following vitrectomy. A previous RNA study was limited by low RNA quality and batch variation. We conducted a new prospective RNA-sequencing study of human lens epithelial cells in post-vitrectomy and age-related cataract to compare gene expression profiles.
Methods :
Sample collection occurred from March to July 2023 in Melbourne, Australia. Human lens capsule specimens from post-vitrectomy (n=13), and age-related (n=33) cataracts were collected at the time of cataract surgery. Samples were stabilized in RNAlater prior to RNA extraction with RNeasy Mini. Quality control was performed with Agilent 2200 TapeStation. RNA isolation and library preparation occurred at Australian Genome Research Facility. Differentially expressed genes (DEGs) were identified as those with log2 fold change>1 and false discovery rate <0.05 and underwent bioinformatics analyses.
Results :
17393 genes were included in the analysis after low abundant genes were removed. Diabetes and glucocorticoid use were identified as covariates and corrected for in the analysis. We identified 220 DEGs with 208 upregulated and 12 downregulated DEGs in post-vitrectomy cataract compared to age related cataract. Significant upregulated gene ontology pathways included: response to external stimulus (71 genes, p<6.0E-17), collagen-containing extracellular matrix (34 genes, GR 0.11, p<8.5E-23) and inflammatory response (36 genes, p<1.1E-15). Significant upregulated Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways included: complement and coagulation cascades (11 genes, p<6.3E-11) and advanced glycation product (AGE)/receptor for AGEs signaling pathway in diabetic complications (10 genes, p<1.7E-7), which has been shown to induce oxidative stress. Gene Set Enrichment Analysis (GSEA) indicated upregulated TNF alpha signaling via NFκB upregulation (181 genes, p<1.4E-14) and upregulated epithelial mesenchymal transition (189 genes, p<2.9E-13).
Conclusions :
Our findings suggest post-vitrectomy cataract has a different transcriptomic profile to age related cataract. Upregulated pathways in response to external stimuli, inflammation, oxidative stress, and epithelial misregulation may be implicated in accelerated cataract development in post vitrectomy eyes.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.