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bioRxiv · 10.1101/2021.10.29.466419

Identifying Lethal Dependencies with HUGE Predictive Power from Large-Scale Functional Genomic Screens

Abstract

Recent functional genomic screens -such as CRISPR-Cas9 or RNAi screening-have fostered a new wave of targeted treatments based on the concept of synthetic lethality. These approaches identified LEthal Dependencies (LEDs) by estimating the effect of genetic events on cell viability. The multiple-hypothesis problem related to the large number of gene knockouts limits the statistical power of these studies. Here, we show that predictions of LEDs from functional screens can be dramatically improved by incorporating the "HUb effect in Genetic Essentiality" (HUGE) of gene alterations. We analyze three recent genome-wide loss-of-function screens - Project Score, CERES score and DEMETER score-identifying LEDs with 75 times larger statistical power than using state-of-the-art methods. HUGE shows an increased enrichment in a recent harmonized knowledgebase of clinical interpretations of somatic genomic variants in cancer (with an AUROC up to 0.87). Our approach is effective even in tumors with large genetic heterogeneity such as acute myeloid leukemia, where we identified LEDs not recalled by previous pipelines, including FLT3-mutant genotypes sensitive to FLT3 inhibitors. Interestingly, in-vitro validations confirm lethal dependencies of either NRAS or PTPN11 depending on the NRAS mutational status. HUGE will hopefully help discover novel genetic dependencies amenable for precision-targeted therapies in cancer.

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BibTeXRIS

Carazo, F., San Jose Eneriz, E., Gimeno, M., Garate, L., Miranda, E., Castilla, C., Agirre, X., Rubio, A., Prosper, F.. 2021-11-01. Identifying Lethal Dependencies with HUGE Predictive Power from Large-Scale Functional Genomic Screens. https://doi.org/10.1101/2021.10.29.466419

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