Table 4.

Effect of AG14361 on repair of camptothecin-induced DNA strand breaks in K562 cells

Time after camptothecin removal% Unrepaired DNA
Fold increase in strand breaks
CamptothecinCamptothecin + 0.4 μmol/L AG14361
Camptothecin (30 nmol/L)
    0100100
    10 min20 ± 5.450 ± 1.7*2.5 ± 0.2
    20 min16 ± 2.822 ± 4.91.4 ± 0.4
Camptothecin (300 nmol/L)
    0100100
    1 h15 ± 5.544 ± 5.11.9 ± 0.1
    16 h10 ± 9.639 ± 6.22.5 ± 0.85
  • NOTE: K562 cells were exposed to 30 or 300 nmol/L camptothecin for 30 minutes followed by repair in drug-free (control) medium or medium containing 0.4 μmol/L AG14361 for the times indicated. DNA strand breaks were measured by alkaline elution. Relative elution was calculated by comparison with DMSO or 0.4 μmol/L AG14361 alone control as appropriate. Mean ± SE of three independent experiments.

  • * P < 0.005, Student's paired t test compared with camptothecin alone.

  • P = 0.07, Student's paired t test compared with camptothecin alone.

  • P = 0.02, Student's paired t test compared with camptothecin alone.