TABLE 2.

Growth inhibition induced by Hsp90 inhibitors in human breast cancer cell lines dependent upon NQO1 activity

Data expressed as mean ± S.D. of three independent experiments.

Compound	IC50		IC50-Fold Difference
	MDA468	MDA468/NQ16
	µM
GA	0.06 ± 0.01	0.02 ± 0.01	3
19Ph-GA	7.45 ± 0.51	1.19 ± 0.08	6
17-AAG	10.05 ± 1.07	0.86 ± 0.16	11
19Ph-AAG	88.37 ± 2.46	38.79 ± 10.90	2
17-DMAG	0.61 ± 0.02	0.19 ± 0.02	3
19Ph-DMAG	16.48 ± 2.14	3.28 ± 0.26	5