Table 1.

Binding and inhibitory activities of selected HDACi on different HDAC4 variants

Compound	Binding assay HDAC4-F + CD	Histone assay HDAC4-F*	Biomol assay HDAC4-F*	Biomol assay mHDAC4-F†	Biomol assay mHDAC4-CD†
MS-275	−	510 (±62)	3,017 (±422)	NA up to 10,000	NA up to 10,000
Apicidin	−	2.4 (±0.5)	1.2 (±0.3)	NA up to 10,000	NA up to 10,000
Open Apicidin	−	152 (±24)	88 (±11)	NA up to10,000	NA up to 10,000
LAQ824	+	4 (±1.3)	1 (±0.5)	3 (±0.8)	2.5 (±0.7)

IC₅₀ values (nM) are the means of at least two independent experiments. NA, not active.

*[HDAC4-F] was 15 nM; in these assays endogenous class I HDAC activity is measured.

^†[mHDAC4] was 1 nM.