4-iodo-SAHA (Synonyms: ISAHA)

4-iodo-SAHA is a hydrophobic derivative of SAHA, the class I and class II histone deacetylase (HDAC) inhibitor [1].

The reversible acetylation of lysine residues in histone plays an important role in transcriptional activation and repression. The regulation of these post-translational modifications is balanced by histone acetyltransferase (HAT) and histone deacetylase (HDAC) activities. HDACs are also involved in reversible acetylation of non-histone proteins [1].

4-iodo-SAHA is a histone deacetylase (HDAC) inhibitor. In SKBR3-breast-derived cell line, 4-iodo-SAHA inhibited cell proliferation with EC50 value of 1.1 μM. In HT29 colon-derived cell line, leukemia-derived U937 tumor cell line, JA16, HL60 and K562 cell lines, 4-iodo-SAHA inhibited cell proliferation with EC50 values of 0.95, 0.12, 0.24, 0.85 and 1.3 μM, respectively. 4-iodo-SAHA is 10-fold more potent as an inhibitor of U937 leukemia cell proliferation compared to SAHA (0.12 μM versus 1.2 μM). In SKBR3 cells, 4-iodo-SAHA reduced acetylated H4 and p21 levels [1].

Reference:
[1].  Salmi-Smail C, Fabre A, Dequiedt F, et al. Modified cap group suberoylanilide hydroxamic acid histone deacetylase inhibitor derivatives reveal improved selective antileukemic activity. J Med Chem. 2010 Apr 22;53(8):3038-47.