Epithin can degrade Tie2 in a trans fashion. (A) For the coculture of 427.1.86 or 427 Epi-KD cells with MS1 cells (lanes 1 and 2), 2 types of cells were mixed together and cocultured. Eighteen hours after plating, the cells were lysed and analyzed by Western blotting for Tie2, VEGFR-1, epithin, and tubulin. (B) MS1 cells on a gelatin-coated coverslip were transferred into a culture dish containing 427.1.86 or 427 Epi-KD cells and were cocultured for 18 hours. MS1 cells were lysed and analyzed by Western blotting for Tie2 and tubulin. Schematic drawings of each coculture experiment are shown.