Table 1

Flavopiridol resistance in Pgp-, MRP-, and ABCG2-overexpressing cell lines

Cell lineResistance mechanismIC50a (nm)RRb
SW62096.7 ± 6.33
SW620 Ad300Pgp142 ± 3.211.5
S174.4 ± 5.88
S1-B1-20Pgp64.7 ± 6.770.87
S1-M1-80ABCG2460 ± 23.16.2
MCF-787.2 ± 13.3
MCF-7/VPMRP97.3 ± 12.61.1
MCF-7 AdVp3000ABCG23100 ± 29835.6
  • a IC50 values were determined by the sulforhodamine B assay.

  • b Relative resistance values were determined by dividing the IC50 for the resistant cell line by the IC50 for the parental cell line. Experiments were performed at least three times.