The downregulation of EphA2 and EphA3 was investigated as described previously.43 (link) Western blots for testing the presence of receptors were also performed as described previously.9 (link) Three independent experiments were performed for each QUAD version and the EphA2 and EphA3 receptors. Density of immunoreactive bands was measured on an AI600 RGB imager (GE). Data from 3 independent experiments were normalized to the corresponding β-actin and analyzed in Prism GraphPad.