K562 cells were treated with 5 mM benzamide for different times (0-48 h) and the slides were prepared as described in methods. After staining the slides with ethidium bromide, damaged and undamaged cells were identified under a Nikon fluorescent microscope, and subjected to image analysis using comet assay software programme (CASP). DNA damage was quantified by tail moment measurement, calculated by multiplying the total intensity of the comet tail by the tail length, measured from the center of the comet head. A, typical picture of comets in K562 cells treated with 5 mM benzamide for different time point; I, II and III represent typical comets obtained at 0 h, 6 h, and 48 h. B: graphical representation of calculated tail moment at different time points in cells treated with 5 mM benzamide.
