Mouse Tumor-Associated Endothelial Cells (Mouse Colon Cancer Origin, MTCLECH) from Creative Bioarray were isolated from pathogen-free laboratory nude mice. MTCLECH from Creative Bioarray were isolated from human xenograft of pathogen-free laboratory nude mice. Mouse Colon adenocarcinoma epithelial cells (HCT116) were subcutaneously injected into the nude mice for 4-6 weeks and the tumor tissues were then harvested for cell culture. MTCLECH were cultured in a T25 tissue culture flask pre-coated with gelatin-based coating solution for 2 min and incubated in Creative Bioarray' Culture Complete Growth Medium generally for 14-35 days. Cells were detached from flasks and immediately cryo-preserved in vials. Cells will be delivered in a frozen vial and each vial contains 0.5x10^6 cells/ml. The method we use to isolate tumor-associated endothelial cells was developed based on a combination of established and our proprietary methods. These cells are pre-coated with PECAM-1 antibody, following the application of magnetic beads pre-coated with secondary antibody.