Abstract
EGFR-mutant NSCLCs frequently respond to EGFR tyrosine kinase inhibitors (TKIs). However, the responses are not durable, and the magnitude of tumor regression is variable, suggesting the existence of genetic modifiers of EGFR dependency. Here, we applied a genome-wide CRISPR-Cas9 screening to identify genetic determinants of EGFR TKI sensitivity and uncovered putative candidates. We show that knockout of RIC8A, essential for G-alpha protein activation, enhanced EGFR TKI-induced cell death. Mechanistically, we demonstrate that RIC8A is a positive regulator of YAP signaling, activation of which rescued the EGFR TKI sensitizing phenotype resulting from RIC8A knockout. We also show that knockout of ARIH2, or other components in the Cullin-5 E3 complex, conferred resistance to EGFR inhibition, in part by promoting nascent protein synthesis through METAP2. Together, these data uncover a spectrum of previously unidentified regulators of EGFR TKI sensitivity in EGFR-mutant human NSCLC, providing insights into the heterogeneity of EGFR TKI treatment responses.
Data availability
The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD014198. CRISPR-Cas9 screen data were summarized in Supplementary File 1 and Supplementary File 2.
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Funding
No external funding was received for this work.
Ethics
Animal experimentation: All animal work was performed in accordance with Novartis Animal Care and Use Committee (ACUC) regulations and guidelines (reference number 120137). All animals were allowed to acclimate in the Novartis animal facility with access to food and water ad libitum for 3 days prior to manipulation. All cell lines were confirmed as mycoplasma- and rodent pathogens-negative (IMPACT VIII PCR Profile, IDEXX) before implantation.
Copyright
© 2019, Zeng et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Genome-wide CRISPR screening reveals genetic modifiers of mutant EGFR dependence in human NSCLC
eLife 8:e50223.
https://doi.org/10.7554/eLife.50223
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