library_construction_protocol: Genomic DNA was extracted from pellets of 20-50x10^6 cells using the QIAamp Blood Maxi kit (Cat#51194) The Toronto KnockOut (TKO) CRISPR Library - Version 1 (90K sub-library) was used (addgene catalog# 1000000069). Protocol of library construction is detailed in Hart et al. High-Resolution CRISPR Screens Reveal Fitness Genes and Genotype-Specific Cancer Liabilities. Cell. 2015;163(6):1515-26. Pooled genome-wide CRISPR/Ca9 knockout screen