Table 2.

Comparison of lapatinib concentrations that achieve IC50 and the corresponding levels of HER-2 and EGFR expression as measured by ELISA between HER-2 and control-transfected breast cancer cell lines

Cell lineIC50 (SE), μmol/LHER-2 (SE), ng/mgEGFR (SE), ng/mg
MCF-7/CON13.6 (0.8)3.6 (1.5)0.6 (0.2)
MCF-7/HER-24.4 * (1.1)352 (46)0.1 (0.1)
T47D/CON4.0 (0.4)56 (21)0.6 (0.2)
T47D/HER-22.0 * (0.3)229 (23)20 (8.6)
ZR-75-1/CON7.1 (0.5)69 (64)3.1 (0.4)
ZR-75-1/HER-21.7 * (63)581 (63)2.4 (0.5)
  • * Significant difference.