TABLE 1

IC50a values of DPT, PTX, and etoposide in MCF-7/S and MCF-7/A cells

MCF-7/SMCF-7/AResistance Indexb
IC50 (nM)IC50 (nM)
DPT10.61 ± 1.095.86 ± 0.300.552
PTX7.005 ± 0.4455285 ± 1095754.5
Etoposide17,355 ± 2695675,780 ± 10,45038.94
  • a Drug concentration required to inhibit cancer cell proliferation by 50%. Data are expressed as the mean ± S.D. from the dose-response curves of three independent experiments.

  • b Resistance index: (IC50 of MCF-7/A cell)/(IC50 of MCF-7/S cell).