The novel anti-cancer Pan-Ras-In-1 showed remarkable bactericidal activity against S. aureus, which is a novel therapeutic approach to address antimicrobial resistance dilemma in cancer patients with S. aureus infections. The advanced peptide-centric local stability assay (PELSA) was applied help us to figure out the target of Pan-Ras-In-1 to eliminate Staphylococcus aureus.