Table 1.

Profile of KB-3-1 cells selected for resistance to paclitaxel

CompoundIC50 (nmol/L)*, KB-3-1IC50 (nmol/L), KB-15-PTX/099Relative resistanceIC50 (nmol/L), KB-15-PTXRelative resistance
Microtubule-polymerizing agents
    Paclitaxel2.4 ± 0.444.2 ± 16.918.271.2 ± 17.629.3
    Docetaxel0.84 ± 0.464.1 ± 1.84.98.1 ± 1.99.7
    MAC-3210.57 ± 0.062.3 ± 0.23.91.1 ± 0.62.0
    Epothilone B0.61 ± 0.032.1 ± 0.13.40.84 ± 0.011.4
Microtubule-depolymerizing agents
    Vinblastine0.82 ± 0.270.21 ± 0.040.33.0 ± 1.63.7
    HTI-2860.61 ± 0.110.20 ± 0.040.30.52 ± 0.080.8
    Dolastatin-100.041 ± 0.0100.012 ± 0.0040.3NDND
DNA-damaging agents
    Mitoxantrone7.7 ± 2.023.6 ± 4.13.113.5 ± 3.11.8
    Adriamycin56.5 ± 41.376.0 ± 20.01.4NDND
    Bisantrene68.9 ± 45.257.8 ± 46.50.8764 ± 10711.1
  • Abbreviation: ND, not determined.

  • * Mean IC50 (nmol/L) ± SD from two to six independent determinations.

  • Relative resistance = ratio of IC50 of the resistant cell line to IC50 of the parental line.