Antagonist activity at full-length FLAG-tagged XIAP (unknown origin) transfected in HEK293 cells assessed as inhibition of interaction with caspase 9 after 2 hrs by immunoprecipitation assay
Reduction of cIAP1 level in human MDA-MB-231 cells xenografted in Balb/c SCID mouse at 100 mg/kg, ip measured after 1 to 6 hrs by Western blot analysis relative to vehicle-treated control
Reduction of cIAP1 level in human MDA-MB-231 cells xenografted in Balb/c SCID mouse at 100 mg/kg, ip measured after 1 hr by MSD plate-based method relative to vehicle-treated control
Reduction of XIAP level in human MDA-MB-231 cells xenografted in Balb/c SCID mouse at 100 mg/kg, ip measured after 1 to 24 hrs by Western blot analysis
Increase in cleaved PARP level in human MDA-MB-231 cells xenografted in Balb/c SCID mouse at 100 mg/kg, ip measured after 1 to 24 hrs by Western blot analysis
Increase in cleaved caspase-3 level in human MDA-MB-231 cells xenografted in Balb/c SCID mouse at 100 mg/kg, ip measured after 1 to 24 hrs by Western blot analysis
Antitumor activity against human MDA-MB-231 cells xenografted in Balb/c SCID mouse assessed as tumor growth inhibition at 100 mg/kg, po bid measured every 3 days
Toxicity in Balb/c SCID mouse xenografted with human MDA-MB-231 cells assessed as effect on body weight at 100 mg/kg, po bid measured everyday during compound dosing
In vitro Competitive Displacement Binding Assays : Modified SMAC peptides and compounds were tested for their ability to displace the fluorescent tracer from either XIAP, clAP-1 or clAP-2. BIR3 domains of clAP-1 , clAP-2 and XIAP were incubated with test compounds or SMAC based peptides and their respective peptide probes (Peptide Protein Research) in assay buffer (50mM Hepes pH 7.5, 0.025% Tween-20, 0.01 % BSA, and 1 mM DTT). Positive controls consisted of BIR3 proteins and tracer (no inhibition) and negative controls contained tracer only (100% inhibition). The samples were incubated at room temperature for 1 hr (XIAP and clAP-2) or 3hrs (clAP-1 ) prior to being read in the BMG Pherastar in Fluorescence Polarization mode (FP 485nm, 520nm, 520nm).
In vitro Competitive Displacement Binding Assays : Modified SMAC peptides and compounds were tested for their ability to displace the fluorescent tracer from either XIAP, clAP-1 or clAP-2. BIR3 domains of clAP-1 , clAP-2 and XIAP were incubated with test compounds or SMAC based peptides and their respective peptide probes (Peptide Protein Research) in assay buffer (50mM Hepes pH 7.5, 0.025% Tween-20, 0.01 % BSA, and 1 mM DTT). Positive controls consisted of BIR3 proteins and tracer (no inhibition) and negative controls contained tracer only (100% inhibition). The samples were incubated at room temperature for 1 hr (XIAP and clAP-2) or 3hrs (clAP-1 ) prior to being read in the BMG Pherastar in Fluorescence Polarization mode (FP 485nm, 520nm, 520nm).