Radicicol是一种ATP酶/激酶抑制剂，对Hsp90、Topo VI和PDK3的IC50值分别为小于1 μM、100 μM和400 μM[1]。

Radicicol可通过阻断ATP结合，抑制Hsp90、Topo VI和PDK3的活性。Radicicol可与PDK3的C端结构域的ATP结合位点结合，与ATP竞争。此种抑制不会导致PDK3结构变化。Radicicol对PDK1和PDK2也具有较弱的抑制能力，对应的IC50值和Ki值分别为230 mM和23 μM[1]。

作为Hsp90的抑制剂，radicicol可下调PPARγ、C/EBPα、FAS和FABP4的表达，导致3T3-L1脂肪细胞中脂肪积累的抑制。Radicicol对细胞周期停滞和PDK1/Akt途径也有效果，进而引起3T3-L1前脂肪细胞的分化抑制。此外，radicicol可在卵巢癌细胞系中增加caspase-8和Bid依赖途径的激活，提高TRAIL诱发的细胞凋亡[2,3]。

参考文献：
[1] Kato M, Li J, Chuang JL, Chuang DT.  Distinct structural mechanisms for inhibition of pyruvate dehydrogenase kinase isoforms by AZD7545, dichloroacetate, and radicicol. Structure. 2007 Aug;15(8):992-1004.
[2] He Y, Li Y, Zhang S, Perry B, Zhao T, Wang Y, Sun C.  Radicicol, a heat shock protein 90 inhibitor, inhibits differentiation and adipogenesis in 3T3-L1 preadipocytes. Biochem Biophys Res Commun. 2013 Jun 28;436(2):169-74.
[3] Kim YJ, Lee SA, Myung SC, Kim W, Lee CS.  Radicicol, an inhibitor of Hsp90, enhances TRAIL-induced apoptosis in human epithelial ovarian carcinoma cells by promoting activation of apoptosis-related proteins. Mol Cell Biochem. 2012 Jan;359(1-2):33-43.