In silico drug repurposing identifies COX-2 as a target for the treatment of neovascular retinal disease – an in vitro study

Abstract

Purpose : Neovascular retinal diseases can lead to rapidly progressive vision loss due to pathological angiogenesis and breakdown of the blood-retinal barrier (BRB). Since treatment with antibodies against vascular endothelial growth factor (VEGF) elicits only a limited response, the development of complementary therapeutic approaches is of immense importance. In an in silico drug repurposing approach, we combined transcriptomic data from in vitro angiogenesis assays and patient samples to identify approved drugs as possible novel therapeutics for neovascular retinal disease. Based on these results, we tested the efficacy of cyclooxygenase (COX) inhibitors and the impact of COX-2 on disease development in vitro.

Methods : In a GSEA-based in silico drug repurposing approach, RNA Seq data of vascular endothelial cells stimulated with VEGF or vehicle in a 3D angiogenesis assay (spheroid sprouting assay) and of PDR membranes were aligned with known targets of approved drugs. Spheroid sprouting assays using HRMVECs (human retinal microvascular endothelial cells) were performed to evaluate the effect of a siRNA-mediated COX-2 knockdown (KD) or COX-1/2 selective inhibitors (amfenac<celecoxib<lumiracoxib) on endothelial cell sprouting. Impedance assays using HRMVECs and ARPE-19 cells were performed to test the effects of prostaglandin E2 (PGE2), COX inhibitors and VEGF on BRB homeostasis.

Results : GSEA-based in silico drug repurposing identified celecoxib, a selective COX-2 inhibitor, as a possible therapeutic agent. Western blot and RNA analyses showed increased expression of COX-2 mRNA and protein levels upon VEGF stimulation, while COX-2 KD significantly reduced sprouting in vitro. Interestingly, unselective as well as selective COX inhibitors diminished sprouting. Impedance measurements of HRMVEC and ARPE-19 cells as a model for BRB integrity revealed changes in impedance following treatment with PGE2 but not VEGF. Lumiracoxib, but not amfenac, reduced PGE2-induced changes.

Conclusions : Transcriptomic data can be used to identify approved therapeutic agents, which can be repurposed for the treatment of retinal disease, while follow-up experiments are necessary to validate identified targets and drugs. This study revealed that the selective COX-2 inhibitor lumiracoxib is able to reduce endothelial sprouting and prevent breakdown of the barrier-function of ARPE-19 cells.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.