Sardar Pasha, Sheik Pran BabuSishtla, KamakshiSulaiman, Rania S.Park, BominaShetty, TruptiShah, FenilFishel, Melissa L.Wikel, James H.Kelley, Mark R.Corson, Timothy W.2019-01-162019-01-162018-10Sardar Pasha, S. P. B.., Sishtla, K., Sulaiman, R. S., Park, B., Shetty, T., Shah, F., ... & Corson, T. W. (2018). Ref-1/APE1 Inhibition with Novel Small Molecules Blocks Ocular Neovascularization. Journal of Pharmacology and Experimental Therapeutics, 367(1), 108-118. https://doi.org/10.1124/jpet.118.248088https://hdl.handle.net/1805/18175Ocular neovascular diseases like wet age-related macular degeneration are a major cause of blindness. Novel therapies are greatly needed for these diseases. One appealing antiangiogenic target is reduction-oxidation factor 1–apurinic/apyrimidinic endonuclease 1 (Ref-1/APE1). This protein can act as a redox-sensitive transcriptional activator for nuclear factor (NF)-κB and other proangiogenic transcription factors. An existing inhibitor of Ref-1’s function, APX3330, previously showed antiangiogenic effects. Here, we developed improved APX3330 derivatives and assessed their antiangiogenic activity. We synthesized APX2009 and APX2014 and demonstrated enhanced inhibition of Ref-1 function in a DNA-binding assay compared with APX3330. Both compounds were antiproliferative against human retinal microvascular endothelial cells (HRECs; GI50 APX2009: 1.1 μM, APX2014: 110 nM) and macaque choroidal endothelial cells (Rf/6a; GI50 APX2009: 26 μM, APX2014: 5.0 μM). Both compounds significantly reduced the ability of HRECs and Rf/6a cells to form tubes at mid-nanomolar concentrations compared with control, and both significantly inhibited HREC and Rf/6a cell migration in a scratch wound assay, reducing NF-κB activation and downstream targets. Ex vivo, APX2009 and APX2014 inhibited choroidal sprouting at low micromolar and high nanomolar concentrations, respectively. In the laser-induced choroidal neovascularization mouse model, intraperitoneal APX2009 treatment significantly decreased lesion volume by 4-fold compared with vehicle (P < 0.0001, ANOVA with Dunnett’s post-hoc tests), without obvious intraocular or systemic toxicity. Thus, Ref-1 inhibition with APX2009 and APX2014 blocks ocular angiogenesis in vitro and ex vivo, and APX2009 is an effective systemic therapy for choroidal neovascularization in vivo, establishing Ref-1 inhibition as a promising therapeutic approach for ocular neovascularization.enAttribution 3.0 United StatesRef-1/APE1 inhibitionocular neovascular diseasesAPX2009Article