HDAC1/3-IN-1 is a selective HDAC1/3 inhibitor with IC₅₀ values of 256 nM and 340.3 nM for HDAC1 and HDAC3, respectively. It increases the proportion of SubG1 cells and induces apoptosis in glioma cells and glioblastoma stem cells, and is used in glioblastoma research.

HDAC1:256 nM, HDAC3:340.3 nM

Methods: HOG, T98G, U87MG, and U251MG glioma cells were treated with HDAC1/3-IN-1 at concentrations ranging from 0.6 to 50 μM for 24–72 hours. Cell proliferation, histone H3 deacetylation, cell cycle, and apoptosis were detected; GG16 and GSC23 glioblastoma stem cells were treated with HDAC1/3-IN-1 for 72 hours, and cell viability was detected.
Results:
1. HDAC1/3-IN-1 inhibited the proliferation of HOG, T98G, U87MG, and U251MG glioma cells in a time-dependent manner. After 72 hours of action in U251MG cells, the GI₅₀ was the lowest, at 0.6 μM.
2. At effective concentrations, HDAC1/3-IN-1 (10.8–50 μM, 24 hours) could inhibit the deacetylation of histone H3 in HOG, T98G, and U251MG cells.
3. HDAC1/3-IN-1 (10.8–50 μM, 24 hours) could induce the accumulation of T98G and U251MG cells in the SubG1 phase, suggesting the occurrence of DNA fragmentation and apoptosis, and could regulate the cell cycle distribution of glioma cells.
4. HDAC1/3-IN-1 (10.8–50 μM, 24 hours) could induce early apoptosis in HOG, T98G, U87MG, and U251MG cells.
5. After 72 hours of treatment with HDAC1/3-IN-1, the viability of mesenchymal GG16 and pre-neuronal GSC23 glioblastoma stem cells was inhibited, with IC₅₀ values of 2.079 μM and 1.851 μM, respectively [1].