An engineered chimeric toxin that cleaves activated mutant and wild-type RAS inhibits tumor growth
Vania Vidimar, Greg L. Beilhartz, Minyoung Park, Marco Biancucci, Matthew B. Kieffer, David Gius, Roman A. Melnyk, K.J.F. Satchell
Abstract
Significance RAS oncoproteins have long been considered among the most elusive drug targets in cancer research. At issue is the lack of accessible drug-binding sites and the extreme affinity for GTP. Covalent inhibitors against the KRAS G12C mutant have shown early clinical promise; however, targeting the other oncogenic RAS mutants across three RAS isoforms has proven challenging. Inhibition of activated wild-type RAS in the absence of canonical RAS mutations is also highly desirable in certain tumors. Here, we demonstrate delivery of an extremely potent pan-RAS and RAP1-cleaving enzyme in therapeutic quantities to specific receptor-bearing cells in vitro and in vivo. We aim to advance this approach to engineer the first targeted pan-RAS inhibitor for cancer therapy.