Table 2. Concentration (ng/mL) of 2, 9, and 10 in the Culture Media after Incubation of 7 and 8 with Cancer Cell Lines^a.

	prodrug 7				prodrug 8
	MDA-MB-231		HeLa		MDA-MB-231		HeLa
day	2	10	2	10	2	9	2	9
1	30.7 ± 0.4	331.8 ± 4.5	8.4 ± 0.1	282.7 ± 14.2	NF	359.1 ± 13.7	NF	303.2 ± 24.1
2	27.7 ± 1.3	268.5 ± 2.2	6.6 ± 0.1	147.4 ± 3.3	NF	262.9 ± 10.9	NF	188.6 ± 3.9
3	20.3 ± 0.5	246.9 ± 11.2	13.4 ± 0.5	144.9 ± 0.8	NF	199.0 ± 16.1	NF	147.9 ± 8.3
4	19.8 ± 0.9	171.8 ± 3.8	7.8 ± 0.1	107.0 ± 0.7	NF	198.8 ± 13.5	NF	134.7 ± 3.1
5	28.5 ± 1.0	145.8 ± 3.2	3.7 ± 0.2	82.7 ± 3.6	NF	168.5 ± 3.8	NF	97.2 ± 3.8
6	27.8 ± 0.5	130.9 ± 5.4	3.8 ± 0.2	49.6 ± 0.9	NF	155.8 ± 6.5	NF	66.6 ± 1.3

^aNF: no belinostat found. ±: standard error (SEM) of triplicate experiments.