Lipopolysaccharide-Binding Motif Derived Peptides Induce Cell Membrane Damages in Human Lung Cancer and Hepatoma Cell Lines

The LPSBD0 and LPSBD2 peptides, two β-hairpin cationic amphiphilic peptides, exhibit membrane damage and anti-proliferative activities on the A549 (lung cancer) and Hep3B (hepatoma) cell lines were characterized in this study. Light microscopy observations indicate that both peptides induce the production of debris in the cell cultures. The amount of this debris increased in a LPSBD treatment dosage-dependent manner. This debris was also observed by scanning electron microscopy and flow cytometry. As determined by confocal laser microscopy and flow cytometry, cell membrane damage led to Annexin V permeability on the two cancer cell lines used in this study. Both peptide treatments also induced apoptosis in lung and liver cancer cell lines. However, little hemolysis was observed in the hemolytic assay using rat erythrocytes after very-high-dose treatments for both peptides. These results suggest that the two peptides may have the potential to be developed as anti-cancer peptides for human hepatoma and lung cancers.