Formosanin C (Polyphyllin B) is a compound isolated from Rhizoma Paridis, showed pro-apoptosis and immunoregulation with antitumor activity in cultured cells and animal systems.

通过使用caspase-2抑制剂(Z-VDVAC)减轻formosanin C引起的Deltapsi(m)变化，表明caspase-2作用于线粒体上游。使用透过性转换孔抑制剂（cyclosporine A）或caspase-9抑制剂（Z-LEHD）阻断formosanin C诱导的凋亡过程，证明了在formosanin C引发的HT-29细胞凋亡中，线粒体和caspase-9的必要性。

The enzyme activity and kinetics of the purified ROCK1(3-543) are determined using scintillation proximity assay. In this assay, purified ROCK1 is incubated with peptide substrate (Biotin-Ahx-AKRRLSSLRA-CONH2), and 33ATP and the subsequent incorporation of 33P into the peptide is quantified by streptavidin bead capture. For IC50 determination, test compounds are dissolved at 10 mM in 100% DMSO, with subsequent serial dilution in 100% DMSO. Compounds are typically assayed over an 11-point dilution range with a concentration in the assay of 10 μM to 0.2 nM in 3-fold dilutions. For dose-response curves, data are normalized and expressed as percentage inhibition using the formula 100×[(U-C1)/(C2-C1)], where U is the unknown value, C1 is the average of the high signal (0%) control wells, and C2 is the average of the low signal (100%) control wells. Curve fitting is performed The results for each compound are recorded as pIC50 values[1].