Figure 4.

AURKA suppresses the degradation of Survivin in gastric cancer cells. (a and b) AGS and BGC823 cells stably expressing doxycycline-inducible shAURKA or control cells were cultured in the presence of 1 μg/ml doxycycline. Forty-eight hours after induction, cells treated with 100 μg/ml cycloheximide for indicated times and cell lysates were immunoblotted with the indicated antibodies. Densitometry was used to quantify the Survivin and GAPDH levels. The relative expression shown (right panel) are means±s.d. of the ratios of Survivin to GAPDH. (c) BGC823 cells were treated with indicated doses of VX-680, with or without MG132 for 12 h before subjected to western blot analysis with Survivin and GAPDH antibodies. (d) BGC823 cells stably expressing doxycycline-inducible shAURKA or control cells were transfected with His-ubiquitin plasmid and cultured in the presence of 1 μg/ml doxycycline. Twenty-four hours after induction, cells were treated with 10 μm MG132 for 6 h and subjected to immunoprecipitation with Survivin antibody. Survivin immunoprecipitates and inputs (1/10 of IP) were subjected to Western blot analysis with the indicated antibodies. Western blots are representative of three independent experiments.