HDAC inhibition assays

HDAC inhibition assays were performed by Reaction Biology Corp. using isolated human, recombinant full-length HDAC1 and -6 from a baculovirus expression system in Sf9 cells. An acetylated fluorogenic peptide, RHKKAc, derived from residues 379 ~ 382 of p53 was used as substrate. The reaction buffer was made up of 50 mM Tris-HCl pH 8.0, 127 mM NaCl, 2.7 mM KCl, 1 mM MgCl2, 1 mg/mL BSA, and a final concentration of 1% DMSO. Compounds were delivered in DMSO and delivered to enzyme mixture with preincubation of 5 ~ 10 mins followed by substrate addition and incubation for 2 hrs at 30 ℃. Trichostatin A and developer were added to quench the reaction and generate fluorescence, respectively. Dose-response curves were generated starting at 30 μM compound with three-fold serial dilutions to generate a 10-dose plot. IC50 values were then generated from the resulting plots, and the values expressed were the average of duplicate trials ± standard deviation.

Cell lines

B16 murine melanoma cells

Preparation method

The solubility of this compound in DMSO is >10 mM. General tips for obtaining a higher concentration: Please warm the tube at 37 ℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below - 20 ℃ for several months.

Reacting condition

100 μM; 48 hrs

Applications

In B16 murine melanoma cells, Nexturastat A dose-dependently elevated acetyl α-tubulin levels without increasing histone H3 acetylation. Moreover, Nexturastat A potently inhibited the growth of B16 melanoma cells, with the GI50 value of 14.3 μM.

Nexturastat A is a selective inhibitor of histone deacetylase 6 (HDAC6) with IC50 value of 5.2 nM [1].

Nexturastat A is a HDAC inhibitor. It was developed by structural modification of aryl urea HDACIs. The inhibitory activity of Nexturastat A is most potent against HDAC6 with IC50 value of 5.2 nM. Besides that, Nexturastat A also shows inhibition of other HDACs with IC50 values of 3.02, 6.92, 6.68, 9.39, 11.7, 4.46, 0.954, 6.72, 7.57 and 5.14 μM for HDAC1, 2, 3, 4, 5, 7, 8, 9, 10 and 11, respectively. Nexturastat A has been shown to suppress cell proliferation and promote apoptosis in B16 murine melanoma cells [1, 2].

References:
[1] Kalin J H, Bergman J A. Development and therapeutic implications of selective histone deacetylase 6 inhibitors. Journal of medicinal chemistry, 2013, 56(16): 6297-6313.
[2] Zhang L, Han Y, Jiang Q, et al. Trend of Histone Deacetylase Inhibitors in Cancer Therapy: Isoform Selectivity or Multitargeted Strategy. Medicinal research reviews, 2014.