title: Enhanced antitumor activity and selectivity of lactoferrin-derived peptides.
abstract: A number of peptide analogs derived from the N-terminal alpha-helical region of bovine lactoferrin (LFB 14-31), were designed in order to investigate how deviating numbers and positions of positively charged residues and numbers of aromatic residues affected their activity against prokaryotic, normal and transformed eukaryotic cells. Most of the LFB derivatives were highly active against both Escherichia coli and Staphylococcus aureus. The peptides were more active against the tumor cell lines MethA, HT-29 and MT-1 than normal eukaryotic cells. The peptides that were most active against the tumor cell lines had all cationic residues concentrated in one sector of the helical structure. These peptides were less selective against the tumor cell lines than against normal fibroblasts. Quantitative structure-activity relationship studies showed that certain structural parameters affected toxicity against the tumor cell lines more than against fibroblasts. Peptides encompassing these parameters were slightly less active against tumor cells, but gained significant selectivity.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D001943:Breast Neoplasms / Q000473:pathology; D002942:Circular Dichroism; D015195:Drug Design; D004926:Escherichia coli / Q000187:drug effects; D005347:Fibroblasts; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007781:Lactoferrin / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D051379:Mice; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology* / Q000633:toxicity; D021281:Quantitative Structure-Activity Relationship; D013211:Staphylococcus aureus / Q000187:drug effects; D013379:Substrate Specificity; D014407:Tumor Cells, Cultured
chemical_list: D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D010446:Peptide Fragments; D007781:Lactoferrin