Table 2

Cytotoxicity of antimitotic agents in a Taxol-resistant cell line that does not express P-glycoprotein

Cell linesIC50 (nm)a
TaxolEpoAEpoBEleuDiscoVBLCLC
A5492 ± 0.14b6.4 ± 2.00.7 ± 0.114 ± 2.88.1 ± 0.141.8 ± 0.2133 ± 10.6
A549-T12c18.7 ± 0.934 ± 3.13.3 ± 0.7269 ± 11.36.5 ± 2.41.8 ± 0.1833 ± 12.7
Fold resistantd9.45.34.74.90.81.01.0
  • a IC50, drug concentration that inhibits cell division by 50% after 72 h. EpoA, epothilone A; EpoB, epothilone B; Eleu, eleutherobin; Disco, discodermolide; VBL, vinblastine; CLC, colchicine.

  • b Mean ± SE.

  • c Cells were maintained in 2 nm Taxol during cross-resistance experiments.

  • d Ratio of IC50 for A549-T12 resistant cell line to that for the A549 sensitive cell line.