Metastatic cell detection using a phage-peptide-modified light-addressable potentiometric sensor

Detection of metastatic cells is clinically demanded to diagnose metastasis in the early stage and access the therapeutic response to anticancer drugs. We applied phage display technology to cultured cells with different metastasis potentials and obtained four metastasis-associated peptides. The association between peptides and metastatic cells was validated by ELISA as well as biosensor studies. The selected phage-peptides not only bound SW620, the metastatic cell against which the peptides were screened, but were also able to capture breast cancer cells of high metastasis. The phage-peptide-modified LAPS (light-addressable potentiometric sensor) was able to distinguish metastatic cells from non-metastatic cells and detect as few as 100 metastatic cells per ml of blood. Thus LAPS modified with specific phage-peptides may be developed to provide a new diagnostic approach that can aid the treatment of cancer.