APEX1 and lung adenocarcinoma: Confocal microscopy and superresolution (110-nm) three-dimensional (3D) structured illumination microscopy (SIM) data revealed AcAPE1 staining to be strictly nuclear, whereas unmodified APE1 was observed both in the nucleus and in the cytoplasm in human normal lung fibroblast (IMR90) cells, human telomerase reverse transcriptase (hTERT)-transformed diploid BJ fibroblast cells (BJ-hTERT cells), as well as human lung adenocarcinoma A549 cells (Fig. 1A, B, and D).