Motesanib  (Synonyms: AMG 706)

Optimal enzyme, ATP, and substrate (gastrin peptide) concentrations are established for each enzyme using homogeneous time-resolved fluorescence (HTRF) assays. Motesanib is tested in a 10-point dose-response curve for each enzyme using an ATP concentration of two-thirds K_m for each. Most assays consist of enzyme mixed with kinase reaction buffer [20 mM Tris-HCl (pH 7.5), 10 mM MgCl₂, 5 mM MnCl₂, 100 mM NaCl, 1.5 mM EGTA]. A final concentration of 1 mM DTT, 0.2 mM NaVO₄, and 20 μg/mL BSA is added before each assay. For all assays, 5.75 mg/mL streptavidin-allophycocyanin and 0.1125 nM Eu-PT66 are added immediately before the HTRF reaction. Plates are incubated for 30 minutes at room temperature and read on a Discovery instrument. IC₅₀ values are calculated using the Levenberg-Marquardt algorithm into a four-parameter logistic equation.

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Cells are preincubated for 2 hours with different concentrations of Motesanib, and exposed with 50 ng/mL VEGF or 20 ng/mL bFGF for an additional 72 hours. Cells are washed twice with DPBS, and plates are frozen at -70°C for 24 hours. Proliferation is assessed by the addition of CyQuant dye, and plates are read on a Victor 1420 workstation. IC₅₀ data are calculated using the Levenberg-Marquardt algorithm into a four-parameter logistic equatio.

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

A431 cells are cultured in DMEM (low glucose) with 10% FBS and penicillin/streptomycin/glutamine. Cells are harvested by trypsinization, washed, and adjusted to a concentration of 5×10⁷/mL in serum-free medium. Animals are challenged s.c. with 1×10⁷ cells in 0.2 mL over the left flank. Approximately 10 days thereafter, mice are randomized based on initial tumor volume measurements and treated with either vehicle (Ora-Plus) or Motesanib. Tumor volumes and body weights are recorded twice weekly and/or on the day of sacrifice. Tumor volume is measured with a Pro-Max electronic digital caliper and calculated using the formula length (mm)×width (mm)×height (mm) and expressed in mm³. Data are expressed as mean±SE. Repeated measures ANOVA followed by Scheffe post hoc testing for multiple comparisons is used to evaluate the statistical significance of observed differences.

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

• [1]. Polverino A, et al. AMG 706, an oral, multikinase inhibitor that selectively targets vascular endothelial growth factor, platelet-derived growth factor, and kit receptors, potently inhibits angiogenesis and induces regression in tumor xenografts. Cancer R  [Content Brief]

  [2]. Kruser TJ, et al. Augmentation of radiation response by motesanib, a multikinase inhibitor that targets vascular endothelial growth factor receptors. Clin Cancer Res, 2010, 16(14), 3639-3647.  [Content Brief]

  [3]. Coxon A, et al. Broad antitumor activity in breast cancer xenografts by motesanib, a highly selective, oral inhibitor of vascular endothelial growth factor, platelet-derived growth factor, and Kit receptors. Clin Cancer Res, 2009, 15(1), 110-118.  [Content Brief]