2.8. In Vitro Aurora Kinase Assay

The in vitro aurora kinase assay was performed as described previously (Sheng et al., 2014). Histone H3 and active Aurora kinase B were purchased from Merck Millipore (Billerica, MA). Histone H3 (1 μg) and active Aurora kinase (100 ng) were mixed with different doses of deguelin or hesperadin in a 20 μL reaction, which was conducted in 100 μM ATP and 1 × kinase buffer (Cell Signaling Technology) at 30 °C for 30 min. Reactions were stopped by boiling samples in 5 × SDS loading buffer, and proteins were analyzed by Western blot.