Chidamide,

Details:

Chidamide(CS055; HBI-8000) is a class I HDAC inhibitor with IC50s of 95/160/67/733 nM for HDAC1/2/3/8; also inhibits HDAC10/11(IC50=78/432 nM); no inhibition on HDAC4/5/7/9/6(IC50>30 uM).
IC50 value: 95/160/67/733 nM(HDAC1/2/3/8) [2]
Target: Class I HDAC inhibitor
in vitro:  Chidamide was able to increase the acetylation levels of histone H3 and to inhibit the PI3K/Akt and MAPK/Ras signaling pathways, which resulted in arresting colon cancer cells at the G1 phase of the cell cycle and promoting apoptosis [1]. chidamide inhibited class I HDACs 1–3, as well as class IIb HDAC10, at low nanomolar concentrations. Chidamide significantly induced histone H3 acetylation in both HeLa human cervical adenocarcinoma cells and human PBMC and the extent of induction was similar to that seen with MS-275 and SAHA [2]. Cell growth inhibition studies performed with 18 human-derived tumor cell lines demonstrated that chidamide and MS-275 similarly inhibited the in vitro growth of most, but not all, tumor cells in the low micromolar concentration range [2]. At low concentrations (<1 μM), CS055 induced G1 arrest. At moderate concentrations (0.5 μM-2 μM), CS055 induced differentiation, as determined by the increased expression of the myeloid differentiation marker CD11b. At relatively high concentrations (2 μM-4 μM), CS055 potently induced caspase-dependent apoptosis [3]. Chidamide treatment significantly decreased the expression of type I HDACs, uncleaved Caspase-3 and p21 and increased the ratio of Bax/Bcl-2 expression [4].
in vivo: chidamide in the dose range of 12.5–50 mg/kg dose-dependently reduced tumor size and tumor weight, and the dose of 50 mg/kg produced similar or greater efficacy compared with the control drugs 5-fluorouracil (5-FU, 20 mg/kg) and MS-275 (25 mg/kg, which was reported as the maximum tolerated dose in xenograft models [2]. Daily oral CS055 treatment of nude mice bearing HL60 cell xenografts suppressed tumour growth, induced tumour cell apoptosis and prolonged the survival of tumour-bearing mice [3].