Resminostat hydrochloride (RAS2410 hydrochloride) is an effective inhibitor of HDAC1/HDAC3/HDAC6 (IC50: 42.5/50.1/71.8 nM), respectively, and shows less potent activities against HDAC8 (IC50: 877 nM).

HDAC3:50.1 nM, HDAC6:71.8 nM, HDAC8:877 nM, HDAC1:42.5 nM

Resminostat hydrochloride (5 μM) 在骨髓瘤细胞中诱导组蛋白乙酰化，并且显示具有底物竞争性结合模式（Ki: 27 nM），同时也诱导组蛋白过度乙酰化。Resminostat 抑制细胞生长，诱导凋亡并抑制多发性骨髓瘤（MM）细胞增殖。此外，Resminostat (5 μM) 调节bcl-2家族蛋白的表达，并抑制Akt途径的信号传导。在头颈部鳞状细胞癌细胞系中，Resminostat 抑制细胞生长（对SCC25的IC50为0.775 μM；对CAL27为1.572 μM；对FaDu为0.899 μM）。Resminostat（1.25/2.5 μM）与放射照射联合使用时，对HNSCC细胞线有协同效应。与顺铂联用时，Resminostat 促进了survivin的下调表达。然而，Resminostat 对Mcl-1和p-AKT表达无影响。在与AZD-2014联合治疗下，Resminostat 降低了HCC细胞的活力（IC50s：0.07-0.89 μM）。

Forty microliter enzyme buffer (15 mM Tris HCl pH 8.1, 0.25 mM EDTA, 250 mM NaCl, 10% v:v glycerol) containing HDAC1, 3, 6 or 8 activity, 29 μL enzyme buffer and 1 μL resminostat [HCl] at different concentrations are added to a 96-well microtitre plate and the reaction started by the addition of 30 μL substrate peptide Ac-NH-GGK(Ac)-AMC (HDAC1, 3 and 6 assays, final concentrations 6 μM for HDAC1, 10 μM for HDAC6 and 25 μM for HDAC3/DAD) or Ac-RHK(Ac)K(Ac)-AMC (HDAC8 assay, final concentration 50 μM). After incubation for 180 min (HDAC1, HDAC6, HDAC8) or 120 min (HDAC3) at 30°C, the reaction is terminated by the addition of 25 μL stop solution (50 mM Tris HCl pH 8, 100 mM NaCl, 0.5 mg/mL trypsin and 2 μM trichostatin A [TSA]). After incubation at room temperature for further 40 min, fluorescence is measured using a Wallac Victor2 1420 multilabel counter (extinction 355 nm, emission 460 nm) for quantification of AMC generated by tryptic cleavage of the deacetylated peptide. For the calculation of the 50% inhibitory concentration (IC50) values the fluorescence in wells without test compound (1% DMSO, negative control) is set as 100% enzymatic activity and the fluorescence in wells with 2 μM TSA (positive control) are set at 0% enzymatic activity (background fluorescence substracted).

Resminostat is dissolved in DMSO.A CCK-8 cell proliferation assay is used to investigate the antiproliferative effect of resminostat on HNSCC cells. Cells are seeded into 96-well plates at a density of 3 × 105/well. After 24 hours of growth, the cells are treated with resminostat and cisplatin, either alone or in combination and incubated for 72 hours. Untreated cells maintained in RPMI and equal concentrations of dimethylsulfoxide served as control. After 72 hours, cell proliferation is measured by CCK-8.