Identification and characterization of oncogenic KRAS G12V inhibitory peptides by phage display, molecular docking and molecular dynamic simulation

Abstract

The KRAS G12V mutation is a critical oncogenic driver in aggressive cancers, yet developing effective inhibitors remains challenging due to its elusive structural features. In this study, we employed phage display technology using both linear and cyclic peptide libraries to identify inhibitory peptides against KRAS G12V. Through subtractive bio-panning against wild-type KRAS, we identified two 23-mer peptides (Pep I and Pep II) that demonstrated selective binding to KRAS G12V. Molecular dynamics simulations revealed distinct binding mechanisms - Pep II showed stronger selective binding to G12V (-35.96 kcal/mol) compared to wild-type KRAS (-18.06 kcal/mol), while Pep I exhibited similar binding energies but interacted with different regions. Notably, Pep I bound to functional regions in KRAS G12V but non-functional regions in wild-type KRAS. Both peptides demonstrated significant inhibition of KRAS G12V-carrying cancer cell lines (NCI-H2444 and SW620), reducing cell viability by 70-75 % at 400 μM after 48 h while showing minimal effects (20-30 % reduction) on wild-type KRAS-carrying Caco-2 cells, which is equal to DMSO diluent control. These findings provide new insights into peptide-based targeting of KRAS G12V and demonstrate the potential of using subtractive phage display for developing selective inhibitors against oncogenic mutations.

Keywords: Cancers; KRAS G12V; Targeted therapy; Therapeutic peptide.