DNA damage and repair capacity of PM and CR0 cells exposed to selected chemotherapeutic drugs. Three drugs were tested: (A,B) cisplatin, (C,D) gemcitabine, and (E,F) vinorelbine tartrate. Cells were treated with two selected concentrations of the above chemotherapeutic drugs for 48 h and their DNA damages were measured by comet assay directly or after a 24 h recovery period. Two DNA damage parameters are shown: (A,C,E) % tail DNA and (B,D,F) tail extent moment. Results shown are ratio over untreated PM-control. Error bars represent mean ± SD of three separate experiments. Dash line on the y-axis represents ratio value of PM-control at one.