Fig. 1

Doxorubicin (DOX) induces DNA damage and nuclear DNA leakage. Human breast cancer MDA-MB-231 and MCF-7 cells were treated without or with DOX as indicated. (a) The expression of phospho-H2AX (Ser139) was detected by western blot analysis with GAPDH as loading control. (b) Nuclear DNA leakage was shown by fluorescence microscopy with DAPI staining. Scale bars: 5 μm. (c) The number of DAPI-stained nuclear DNA particles leaked per cell was quantified from 50 cells in three independent experiments. Data was presented as mean ± S.D. (**P < 0.01)