TABLE 4.

Effect of rotenone or antimycin A on the viability, relative resistance, and reversal of resistance of HEK-ABCG2 and parental cells

Compound	IC50		Relative resistancea	Sensitization/reversal of resistanceb
	HEK-293 control	HEK-ABCG2
Rotenone alone	6.9 ± 1.8 nm	4.6 ± 1.6 nm	0.7 ± 0.3-fold
Rotenone + 2 μm curcumin + 35 nm gA	9.3 ± 3.4 nm	4.4 ± 1.5 nm	0.5 ± 0.2-fold	1.4 ± 0.9-fold
Rotenone + 2 μm curcumin + 7.5 nm ouabain	6.4 ± 1.9 nm	4.5 ± 1.4 nm	0.7 ± 0.3-fold	0.9 ± 0.6-fold
Antimycin A alone	6.0 ± 2.1 mm	4.0 ± 2.0 mm	0.7 ± 0.3-fold
Antimycin A + 2 μm curcumin + 35 nm gA	1.6 ± 0.7 mm	1.3 ± 0.4 mm	0.8 ± 0.4-fold	0.8 ± 0.6-fold
Antimycin A + 2 μm curcumin + 7.5 nm ouabain	2.0 ± 1.0 mm	1.8 ± 1.0 mm	0.9 ± 0.6-fold	0.8 ± 0.7-fold

^a Expressed as the ratio of the IC₅₀ value of ABCG2-expressing cells to that of the control cells.

^b Expressed as the ratio of the relative resistance value of ABCG2-expressing cells in the absence of the second compound to the relative resistance in its presence.