Selection and identification of a specific binding peptide targeting to blood vessel of human colon cancer
AIM: To select, identify and analyze a peptide binding specifically to blood vessels of human colon cancer by phage displayed peptide library in vivo. METHODS: Animal models were established using sub-renal capsular assay ( SRCA) in immunosupressed mice implanted with human colon cancer xenografts. The phage displayed peptide library was injected intravenously into mice. After 4 rounds of selection, 20 clones were picked up randomly and sequenced individually. The binding ability to Co-HUVECs of the positive phage clones were determined by in vitro cell ELISA. The binding ability to Co-HUVECs of peptide-displayed phage clone was identified by immunocyto-chemical stain. Immunofluorescence microscopy was used to study the binding of synthesized peptides to Co-HUVECs. RESULTS: Two peptide sequences were obtained finally and named by CV1 and CV2. In vitro cell ELISA suggested that CV2 phage preferably binds to Co-HUVECs rather than control HUVECs. CV1 phage had no marked different binding to Co-HUVECs and HUVECs. Immunocytochemical staining showed that CV2 phage preferably binds to Co-HUVECs rather than control HUVECs and Lovo cells. Fluorescence labeled CV2 peptide was seen on the membrane and in the perinuclear cytoplasm of Co-HUVECs. CONCLUSION: Two phage clones displaying CV1 and CV2 peptide could target to human colon cancer xenografts. The peptide CV2 and its displayed phage were identified binding preferably with Co-HUVECs. The peptide CV2 could be used in target therapy of tumor angiogenesis.
colon cancerphage displayed peptide libraryin vivo screeningangiogenesispeptide
NETL
NSTL
万方数据
维普
