APE1/Ref-1 acts as a reductive activator of many transcription factors involved in apoptosis, inflammation, angiogenesis, and survival pathways [8,9,10,11], and has attracted attention as a biomarker for the diagnosis of various cancers, because it is expressed in malignant tumors and increases in plasma with increasing cancer stage [12,13,14]. The gene discussed is APEX1; the disease is cancer.