Inactivation of multi-RTKs and downstream intermediates by HSP90 inhibition. A) Inhibition of EGFR, ERBB2, ERBB4, AXL and MET phosphorylation in cell immunoprecipitates after 4 h 17-AAG (1 μM) treatment in serum-free medium. B) Immunoblotting evaluated effects of HSP90 inhibitor 17-AAG on RTK EGFR, ERBB2, and MET, and intermediate AKT, S6 and MAPK activation, after 4 h treatment in serum-free medium. C) Effects of HSP90 inhibitor 17-AAG on EGFR, ERBB2, MET, AXL, PCNA, p53, Caspase 8 and PARP expression in ovarian cancer lines, after 48 h 17-AAG treatment in serum-containing medium. β-actin stain is a loading control.