Small RNA Sequencing Reveals a Distinct MicroRNA Signature Between Glucocorticoid Responder (GC-R) and Glucocorticoid Non-responder (GC-NR) Primary Human Trabecular Meshwork Cells after Dexamethasone Treatment
To investigate the role of miRNAs in differential glucocorticoid (GC) responsivenessin human trabecular meshwork (HTM) cells using small RNA sequencing.Human organ-cultured anterior segment (HOCAS) was established with one eye of adonor pair of eyes to characterize the GC responsive eyes based on the IOP change (>5mmHg)and in the other eye, primary HTM cell culture was established. Total RNA was extracted fromcultured HTM cells with known GC responsiveness (GC-responder GC-R; n=4) and GC-non-responder (GC-NR; n=4) for small RNA-seq after treatment with either 100nM dexamethasone(DEX) or ethanol (ETH) for 7 days. Differentially expressed miRNAs (DEMIRs) werecompared among 5 groups (Group #1: ETH vs DEX-treated GC-R; #2: ETH vs DEX-treatedGC-NR; #3: overlapping DEGs between Group #1 and #2; #4: Unique DEMIRs of GC-R and#5: Unique DEMIRs of GC-NR) and validated by qPCR. There were 13 and 21 DEMIRs identified in Group #1 (8 up-regulated; 5 down- regulated) and Group #2 (15 up-regulated; 6 down-regulated), respectively. Seven miRNAs were found as common miRNAs dysregulated in both GC-R and GC-NR (Group #3). In GC-R therewere 6 unique DEMIRs: hsa-miR-2114-3p, hsa-miR-2114-5p were significantly up-regulatedand hsa-miR-335-5p, hsa-miR-549a-5p, hsa-miR-7151-3p and hsa-miR-124-3p weresignificantly down-regulated. Whereas in GC-NR, there were 14 (DEMIRs: hsa-miR-4485-5p,hsa-miR-12136, hsa-miR-4328 were significantly up-regulated and hsa-miR-181b-2-3p, hsa-miR-486-3p and hsa-miR-6853-3p were significantly down-regulated. Ingenuity PathwayAnalysis identified enriched pathways and biological processes associated with differentialglucocorticoid (GC) responsiveness in HTM cells. This is the first study revealed a unique miRNA signature between GC-R and GC- NR HTM cells. Understanding the role of miRNAs in GC responsiveness raises the possibility of new molecular targets for the management of steroid-OHT/glaucoma.