Clinical use and applications of histone deacetylase inhibitors in multiple myeloma

Figures & data

Table 1 Various classes of HDAC

Classification	Homology to yeast	Localization	Remarks
1. Class I
IA – HDAC 1, 2	Yeast Rpd3	Nucleus	Transcriptional regulation
IB – HDAC 3	Yeast Rpd3	Nucleus	Transcriptional regulation
IC – HDAC 8	Yeast Rpd3	Nucleus/cytoplasm	Transcriptional regulation
2. Class II
IIA – HDAC 4,5,7,9	Yeast Hda1 (histone deacetylase 1)	Nucleus/cytoplasm	Tissue-specific functions
IIB – HDAC 6,10	Yeast Hda1	Cytoplasm	Formation of aggresome and autophagy
3. Class III (sirtuins)
SIRT 1, 2, 3, 4, 5, 6, 7	Yeast Sir2 (silent information regulator 2)	Nucleus/mitochondria/cytoplasm	NAD+-dependent lysine deacetylases
4. Class IV
HDAC 11	–	Cytoplasm	Role in interleukin-10 expression

Abbreviations: HDAC, histone deacetylase; NAD+, nicotine adenine dinucleotide positive.

Table 2 Classification of HDAC inhibitors

Classification	Examples	Specificity to HDAC
1. Aliphatic fatty acids	Butyrate	Classes I and IIa
	Valproic acid	Classes I and IIa
2. Hydroxamate	SAHA (vorinostat)	Pan inhibitor
	PXD101 (belinostat)	Pan inhibitor
	LBH589 (panobinostat)	Classes I and II
	ITF2357 (givinostat)	Pan inhibitor
	4SC-201 (resminostat)	Pan inhibitor
	PCI 24781 (abexinostat)	Classes I and II
	Tubacin	Class IIb
3. Benzamides	MS-275 (entinostat)	Class I
	MGCD0103 (mocetinostat)	Class I
	CI-994 (tacedinaline)	Class I
	MGCD-0103	Classes I and IV
4. Cyclic peptides	Depsipeptide/FK228 (romidepsin)	Class I
	Apicidin	Class I
5. Mercaptoketone	KD5170	Classes I and II

Abbreviations: HDAC, histone deacetylase; SAHA, suberoylanilide hydroxamic acid.