APEX1 and neoplasm: Extracts isolated from tumor-adjacent tissues of patients with colon, pancreas, ovarian and lung cancer (Figure S3), as well as resected normal tissues from the ovary, endometrium, fallopian tubes and peripheral blood mononuclear (PBMN) cells of healthy persons (Figure 3E), also demonstrated APE1-specific cleavage activity in this in vitro assay.