Molecular dynamics, thermodynamic, and mutational binding studies for tumor-specific LyP-1 in complex with p32.

Recent studies in tumor homing peptides have shown the specificity of LyP-1 (CGNKRTRGC) to tumor lymphatics. In this present work, we evaluated the possible interactions between cyclic LyP-1 and its receptor, p32, with molecular dynamics and docking studies in order to lead the design of novel LyP-1 derivatives, which could bind to p32 more effectively and perform enhanced antitumor effect. The total binding enthalpy energies have been obtained by MM-PBSA thermodynamic computations and the favorability of p32.LyP-1 complex in water has been shown by explicit water MD computations. The last 30 ns of molecular dynamics trajectory have shown the strong interaction of LyP-1 with the inner surface chains of p32, especially with chains B and C. ALA-SCAN mutagenesis studies have indicated the considerable influence of Asn3, Lys4, Arg5, and Arg7 amino acid residues on the specific binding of LyP-1. Within the knowledge of the critical role of p32 receptor in cancer cell metabolism, this study can lead to further developments in anticancer therapy by targeting p32 with LyP-1 derivatives as active targeting moiety. This data can also be applied for the development of new drug delivery systems in which LyP-1 can be used for its targeting and anticancer properties.