Fluorescence microscope images (A, B, D and E). Untreated and apoptotic cells in LoVo (A, B) and LRWZ (D,E) cells, respectively, afte r a 24-hour exposure to 10 μM and 50 μM of NCX 4040, respectively, as evidenced by DAPI staining. Electrophoresis of genomic DNA samples (C, F). Genomic DNA isolated from LoVo (C) and LRWZ (F) cells after different exposure times to NCX 4040 was electrophoresed on 1.5 % agarose gel to detect internucleosomal DNA fragmentation. (C) (10-μM concentration of NCX 4040): lane a, untreated; lane b, 2-hour exposure; lane c, 4-hour exposure; lane d, 6-hour exposure; lane e, 24-hour exposure. (F) (50-μM concentration of NCX 4040): lane a, untreated; lane b, 2-hour exposure; lane c, 4-hour exposure; lane d, 8-hour exposure; lane e, 16-hour exposure; lane f, 24-hour exposure; lane g, 48-hour exposure.