Acetylation on critical lysine residues of Apurinic/apyrimidinic endonuclease 1 (APE1) in triple negative breast cancers

► A new antibody targeting acetylated K27 to K35 within APE1/Ref-1 is described. ► The antibody detects changes in APE1/Ref-1 acetylation status upon genotoxic insult. ► A cohort of triple negative breast cancer specimens was analyzed with the antibody. ► We report evidence of deregulation in APE1/Ref-1 acetylation in breast cancer. ► This is the first report analyzing APE1 acetylation in human cancers.