Resminostat (4SC-201) is an orally bioavailable inhibitor of histone deacetylases (HDACs) with potential antineoplastic activity.

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

Resminostat显示出良好的PK曲线,具有高生物利用度和低pT变异性.口服Resminostat的表观t 1/2范围为2.7至4.4小时.一天一次口服600 mg Resminostat,在14天的周期内持续1-5天耐受性良好.

Resminostat可激活Caspases 3,8 和9。Resminostat与Melphalan 和Proteasome inhibitors bortezomib 及S-2209有协同作用。Resminostat[HCl]可以诱导MM细胞组蛋白H4的高度乙酰化。 Resminostat可以阻止MM细胞系（OPM-2,NCI-H929,U266）中细胞生长和强力诱导细胞凋亡,同作用于初级MM细胞作用一致。1 μM Resminostat抑制MM细胞系（OPM-2,NCI-H929,U266）细胞增殖和诱导细胞周期的G0/G1期阻滞,同时伴随着cyclin D1,CDC25A,CDK4和Rb的水平降低以及p21基因的上调。Resminostat通过降低4E-BP1和p70S6K的磷酸化来干扰Akt信号通路。Resminostat使Bim和Bax蛋白表达水平升高,Bcl-xL的水平降低。

Enzymatic HDAC activity assays: 40 μL 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 at different concentrations are added to a 96-well microtitre plate and the reaction started by the addition of 30μL 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 3 hours (HDAC1, HDAC6, HDAC8) or 2 hours (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 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 IC50, 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) is set at 0% enzymatic activity (background fluorescence substracted).

Cell lines: OPM-2,NCI-H929,RPMI-8226 and U266. Concentrations: ~ 10 μM. Method: WST-1 assay