Abstract PR12: Genome-wide in-vivo tumor xenograft CRISPR knockout screening for identifying KRAS mutant synthetic lethal interactions

The KRAS oncogene is frequently mutated in many of the most lethal human cancers and has been resistant to targeted therapies, leading to efforts to identify synthetic lethal genetic interactions in large-scale screens. These screens have been carried out largely in in-vitro cell culture systems using RNA interference (RNAi). Functional genomic screening using the bacterial type II clustered regularly interspaced short palindrome repeats and their associated proteins (CRISPR-Cas9) system has proven to be more powerful than RNAi for systematic genomic perturbation due to its simplicity, decreased off-target effects, and the ability to create knockout rather than knockdown phenotypes.We have conducted a genome-wide CRISPR-Cas9 loss-of-function screen with the human GeCKO v2 library directly in-vivo utilizing a paired isogenic human colorectal cell line (HCT116) with and without a KRAS oncogenic mutation (G13D) to identify genes whose knockout results in synthetic lethal interactions in tumor xenografts with mutated KRAS. Compared to cell culture models, tumor xenografts better recapitulate obstacles tumor cells must overcome for continued proliferation including limited accessibility to nutrients and oxygen. Many recent studies have also highlighted the effect of KRAS oncogenic mutations on the rewiring of metabolic pathways to fuel increased tumor growth. Tumor xenografts offer a better screening platform in identifying factors that might exploit these metabolic pathways.Pathw...
Source: Molecular Cancer Therapeutics - Category: Cancer & Oncology Authors: Tags: Finding Synthetic Lethal Interactions through Functional Genomics: Oral Presentations - Proffered Abstracts Source Type: research