Screening peptides binding specifically to colorectal cancer cells from a phage random peptide library.

The aim of this study was to screen for polypeptides binding specifically to LoVo human colorectal cancer cells using a phage-displayed peptide library as a targeting vector for colorectal cancer therapy. Human normal colorectal mucous epithelial cells were applied as absorber cells for subtraction biopanning with a c7c phage display peptide library. Positive phage clones were identified by enzyme-linked immunosorbent assay and immunofluorescence detection; amino acid sequences were deduced by DNA sequencing. After 3 rounds of screening, 5 of 20 phage clones screened positive, showing specific binding to LoVo cells and a conserved RPM motif. Specific peptides against colorectal cancer cells could be obtained from a phage display peptide library and may be used as potential vectors for targeting therapy for colorectal cancer.