Efficacy of inverso isomer of CendR peptide on tumor tissue penetration

C-end rule (CendR) peptides enhance the permeability of tumor blood vessels and tumor tissues via binding to neuropilin-1 (NRP-1), thus aiding in drug delivery. In this study, we selected one of the CendR peptides (sequence RGERPPR) as the parent l-peptide and substituted d-amino acids for the l-amino acids to synthesize its inverso peptide D(RGERPPR). The binding affinity of D(RGERPPR) with NRP-1 and the cellular uptake was significantly higher than that of RGERPPR.280