Table 2. Adjuvant Effect of Compounds 1–4 To Potentiate the Effect of Etoposide in Human AML Cell Lines upon Cotreatment at 72 h.

	AKR1C3	HL-60			KG1a
compd	pIC50	CIa	DRIb	IC50c (μM)	CIa	DRIb	IC50c (μM)
1	7.0	0.44	2.25	0.51	N/A	N/A	N/A
2	6.4	0.38	2.56	0.45	0.42	2.34	2.88
3	7.1	0.28	3.46	0.33	0.16	6.25	1.08
4	7.2	0.45	2.17	0.53	0.37	2.73	2.47
etoposide	N/A	N/A	N/A	1.16	N/A	N/A	6.70

^aCombination index.

^bDose reduction index.

^cCalculated for etoposide + AKR1C3 inhibitor (μM). N/A: not applicable.