Abstract 1673: KRAS dependency, a gene editing approach

Abstract The RAS family genes encode small GTP-binding cytoplasmic proteins that are important signaling molecules. They regulate cell growth, survival and differentiation by coupling receptor activation to downstream effector pathways. Activating mutations of oncogenic RAS pathway genes are frequently detected in human cancers. The role of KRAS in tumor formation is not questionable. It’s implication in tumor maintenance is less well validated. The KRAS dependency is a key question to answer before to develop KRAS inhibitor. Targeted genome editing using CRISPR/Cas9 is a relatively new, revolutionary technology allowing for efficient and directed alterations of the genome. CRISPR is a genome-editing platform that makes use of the bacterially-derived endonuclease Cas9 to introduce DNA double-strand breaks at precise locations in the genome using complementary guide RNAs. These double strand breaks can be repaired by homologous recombination DNA repair mechanisms thank to a donor DNA template. By this way mutations can be introduced at desired loci, DNA fragment can be deleted or introduce at the desired location. We aimed at investigating the KRAS dependence and we applied the CRISPR-Cas9 technology to engineer isogenic cancer cells harboring a “conditional KRAS gene knockout" by exchanging the KRAS endogenous promoter. This promoter replacement approach can be used also to validate new targets. Citation Format: Christophe Marcireau, Fréderic Lacroix, Dietmar Hoffmann, May Cindhuchao, Loreley Calvet, Yvette Ruffin, Laurent Debussche. KRAS dependency, a gene editing approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1673.