Table 2

Effect of Pgp blockade on the degree of PDMP-induced chemosensitization in MCF7/AdrR and MDA435/LCC6MDR1 cells

Fold sensitizationa,b
TaxolVincristine
MCF7/AdrR ± 5 μm PDMP6.486.07
MCF7/AdrR + 1 μg/ml valspodar ± 5 μm PDMP2.001.97
MDA435/LCC6MDR1 ± 5 μm PDMP13.5737.74
MDA435/LCC6MDR1 + 1 μg/ml valspodar ± 5 μm PDMP1.111.16
  • a Cells were incubated with increasing drug concentrations ± 5 μm PDMP and valspodar over 72 h, and viability was analyzed by the MTT assay.

  • b Fold sensitization was calculated as: (Drug IC50 ± PDMP/Drug IC50 + 1 μg/ml valspodar ± PDMP).