In vitro study of cytotoxic and apoptotic effects of inhibitory peptides against mutated K-Ras

Abstract

Ras genes mutations are responsible for approximately 30 % of human cancers. Of these, K-Ras is the most frequently mutated isoform as common mutations in K-Ras leads to the constant activation of downstream effector pathways. Though K-Ras is considered as an important target in some cancers, no anti-Ras therapy has succeeded in clinic and due to the disadvantages of other able therapeutic approaches for cancer therapy, discovering a new effective peptide seems necessary enough. Objective: In this study, we are going to examine cytotoxic effects of newly designed inhibitory peptides on three cancerous cell lines named CACO2 (wild type K-Ras), AGS (K-Ras(G12D)) and Miapaca2 (K-Ras(G12C)). Methods:Plasmid vectors containing the sequence which will lead cells to produce our designed peptides, were ordered and then a recombinant plasmid were obtained with our sequence that transformed to our cell lines. MTT assay has been used to assess cytotoxic effect of our newly designed peptides that their expression had induced using cobalt. the results will be compared between wild type K-Ras gene harboring cancerous cell lines and mutant K-Ras gene cell lines.Results: Newly designed peptides showed cytotoxic effect on cancerous cell lines which contains G12C and G12D mutated K-Ras Conclusion: Our results showed that the computational development based on the Molecular Dynamics simulations is in accordance with experimental results. Moreover, the two designed peptides PM1 and PM2 are capable of inhibiting the growth of mutant K-Ras harboring cancer cells.