apicidin

**Apicidin** is a cyclic tetrapeptide originally isolated from fermentations of *Fusarium* species. It is a cell-permeable, potent, and selective inhibitor of histone deacetylases (HDACs) with strong in vitro activity against Apicomplexan parasites such as *Plasmodium berghei*, *Cryptosporidium parvum*, and *Toxoplasma gondii*[1][6]. Mechanistically, apicidin inhibits HDACs (notably HDAC2, HDAC3, and HDAC6), leading to hyperacetylation of histones, disruption of transcriptional regulation, cell cycle arrest (notably in the G1 phase), and induction of genes such as p21 and gelsolin[4][5][7]. This results in potent antiproliferative effects, apoptosis induction, and differentiation in various cell types, including tumor and leukemia cells[3][5][7]. It has shown both antiprotozoal and antitumor effects in vitro and in vivo, with oral and parenteral efficacy in animal models[1][3][6]. Apicidin has been extensively studied as a research tool and in preclinical therapeutic contexts but is not approved as a human pharmaceutical.

Other names

apicidinapicidin IaCyclo[(2S)-2-amino-8-oxodecanoyl-1-methoxy-L-tryptophyl-L-isoleucyl-(2R)-2-piperidine-carbonyl]Cyclo(8-oxo-L-2-aMinodecanoyl-1-Methoxy-L-tryptophyl-L-isoleucyl-D-2-piperidinecarbonyl)Ccris 9163Ccris9163Ccris-9163apicidin, HDAC inhibitor