TABLE 2.

Effects of neratinib in reversing ABCB1-mediated MDR in transfected cell lines

Cell survival rates were determined with MTT assays, as described under Materials and Methods. Data are the mean ± S.D. of at least three independent experiments performed in triplicate. The fold reversal of MDR was calculated by dividing the IC₅₀ for cells with the anticancer drug in the absence of inhibitor by that in the presence of inhibitor.

Compounds	IC50 (Reversal)
	HEK293/pcDNA3.1	HEK293/ABCB1
	μM (fold)
Doxorubicin	0.074 ± 0.006 (1.00)	1.339 ± 0.130 (1.00)
+ 0.25 μM Neratinib	0.065 ± 0.006 (1.13)	0.756 ± 0.070 (1.77)**
+ 0.5 μM Neratinib	0.079 ± 0.008 (0.94)	0.332 ± 0.027 (4.03)**
+ 1.0 μM Neratinib	0.082 ± 0.007 (0.90)	0.167 ± 0.010 (7.98)**
+ 10 μM Verapamil	0.083 ± 0.008 (0.89)	0.094 ± 0.008 (14.19)**
Cisplatin	2.431 ± 0.27 (1.00)	2.681 ± 0.27 (1.00)
+ 1.0 μM Neratinib	2.263 ± 0.22 (1.07)	2.176 ± 0.22 (1.23)
+ 10 μM Verapamil	2.356 ± 0.23 (1.03)	2.344 ± 0.23 (1.14)

^**P < 0.01 versus the values obtained in the absence of inhibitor.