Hesperadin(IC50=250 nM) effectively inhibits Aurora B. It potently reduces the activity of AMPK, MAPKAP-K1, MKK1, Lck, CHK1 and PHK, but it could not inhibit MKK1 activity in vivo.

Aurora B:250 nM

In HeLa cells, Hesperadin causing defects in mitosis and cytoplasmic division, leading to cell proliferation and polyploidization stopped, because of Aurora B function inhibition during chromosome connection. Addition of 20-100 nM Hesperadin leading to loss of phosphorylation of the mitogenic histone H3 at the Ser10 site. When Hesperadin concentration was 1 μM, other kinases (AMPK, Lck, MKK1, MAPKAP-K1, CHK1, and PHK) activity were significantly reduced.In an in vitro kinase assay, Hesperadin (IC50 = 40 nM) blocked recombinant trypton histone H3 phosphorylation by T. brucei Aurora kinase-1 (TbAUK1) from the pathogenic Trypanosoma brucei. Hesperadin (IC50 = 48 nM) significantly inhibited the growth of cultured infectious blood form (BF) cells, while Hesperadin (IC50 = 550 nM) and weakly inhibited the growth of insect circulation stage (PF) cells.

For the Aurora B kinase assay, HeLa cells are lysed in a buffer containing 50 mM NaCl, then centrifuging at 13,000 rpm for 20 minutes at 4 °C. Discard supernatant, add 15 mL lysis buffer containing 250 mM NaCl in order to obtain active Aurora B kinase. Centrifuging at low-speed supernatant of the latter extract is used for immunoprecipitation. Monoclonal mouse anti–AIM-1, or mouse anti-HA, is coupled to GammaBind Plus Sepharose, and beads are rotated over-end in the extract for 90 minutes at 4 °C. Beads are washed, aliquoted, and washed in kinase buffer (20 mM Tris, pH 7.5, 150 mM NaCl, 10 mM MgCl2, 1 mM DTT, 10 mM NaF). The kinase assay is performed with 10 μL beads in 20 μL kinase buffer containing 5 μg histone H3, 10 μM ATP, 2.5 μCi [γ-32P]ATP, and different concentrations of Hesperadin for 20 minutes at 37 °C.

HeLa cells and PtK1 cells are added Hesperadin 500 nM for 24 and 48 hours.