Table 1

Drug resistances of K562/BCRP, K562/MDR, and KB/MRP cells

Cells were cultured for 5 days with increasing concentrations of anticancer drugs. Cell numbers were measured with a Coulter counter and IC50 values were then determined. The degree of drug resistance is calculated as the IC50 ratio of resistant cells divided by that of the parental cells. The data are represented as mean values ± SD from triplicate determinations.

Parental cellResistant cellDrugDegree of resistance
K562K562/BCRPSN-3824.8 ± 0.63
K562K562/BCRPMitoxantrone10.1 ± 0.27
K562K562/MDRVincristine173 ± 18.7
KB-3-1KB/MRPVP-1610.3 ± 0.60