Sequence optimization of lipid-modified amphiphilic tetrapeptides as anticancer drug carriers

In this study, 19 tetrapeptides, each consisting of four amino acid residues, were designed and modified with oleic acid to serve as amphiphilic dispersants for anticancer drug delivery. The lipid-modified peptides (Ole-pep) were evaluated for their ability to disperse paclitaxel (Ptx), a poorly water-soluble anticancer drug. The water dispersibility of Ptx was significantly increased when peptides with two or more positively or negatively charged functional groups were used as dispersants. One specific Ole-pep demonstrated a critical micelle concentration of 0.0682 × 10^-3 mol/dm³, confirming its excellent amphiphilic properties and capacity to encapsulate Ptx. Cytotoxicity studies in HeLa cells, a cell line derived from human cervical cancer cells, confirmed that the complexes with Ptx were highly cytotoxic regardless of the peptide used. Additionally, the results suggested that certain peptides, particularly those with a high number of Lys residues, exhibited cytotoxicity on their own.