TABLE 2.

Determination of cytotoxicity (IC₅₀) of tiopronin and luperox (tert-butyl hydroperoxide) against GPX knockdown cell lines

SR was calculated as IC₅₀ parental/IC₅₀ MDR cell line.

Cell line	Cytotoxicity (IC50)
	Tiopronin	SR	Luperox
	mm		μm
KB-3-1 NT	17 ± 0.4		119 ± 11
KB-V1 NT	0.6 ± 0.02	29.0	104 ± 5.4
KB-3-1 GPX1	9.9 ± 0.7		39 ± 2.8
KB-V1 GPX1	8.2 ± 0.4	1.2	83 ± 23
KB-3-1 GPX4	9.9 ± 3.9		60 ± 21
KB-V1 GPX4	8.4 ± 0.9	1.2	266 ± 163
KB-3-1 GPX1 + 4	6.4 ± 3.2		21 ± 6.9
KB-V1 GPX1 + 4	4.9 ± 0.7	1.3	38 ± 0.7