Ref-1/APE1 inhibition with novel small molecules blocks ocular neovascularizations

Sheik Pran Babu Sardar Pasha, Kamakshi Sishtla, Rania S. Sulaiman, Bomina Park, Trupti Shetty, Fenil Shah, Melissa L. Fishel, James H. Wikel, Mark R. Kelley, Timothy W. Corson

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Ocular 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 redoxsensitive 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 mM). 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 laserinduced 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.

Original languageEnglish (US)
Pages (from-to)108-118
Number of pages11
JournalJournal of Pharmacology and Experimental Therapeutics
Issue number1
StatePublished - Oct 2018

ASJC Scopus subject areas

  • Molecular Medicine
  • Pharmacology

Fingerprint Dive into the research topics of 'Ref-1/APE1 inhibition with novel small molecules blocks ocular neovascularizations'. Together they form a unique fingerprint.

Cite this