CRISPR overexpression screens identify genes modulating crizotinib sensitivity in ALCL cell lines. (A) Schematic diagram of the CRISPR-dCas9–based overexpression screen for the identification of genes whose activation modifies sensitivity to crizotinib in ALCL cell lines. A crizotinib/DMSO selection pressure is applied, and gDNA is harvested on day 0 and after 14 days of treatment. The sgRNA regions are amplified from gDNA and then analyzed by next-generation, sequencing followed by statistical analyses. (B) Scatterplot showing robust rank aggregation P values calculated using MAGeCK³⁸  and plotted against the fold change in sgRNA enrichment between day-14 DMSO and day-14 crizotinib of genes detected in ≥2 of the 3 (K299/DEL/SUP-M2) ALCL cell lines tested. (C) Fold change in expression levels of the CRISPR screen candidate genes modulated by CRISPR overexpression for 2 sgRNAs relative to nontargeting (NT) control sgRNA determined at baseline in 4 ALK⁺ ALCL cell lines (K299/DEL/SUP-M2/SU-DHL-1) plotted against the total number of gene-specific sgRNAs that modified sensitivity to crizotinib in 48-hour CellTiter-Blue assays. Individual overexpression levels for each sgRNA and for separate ALCL cell lines can be found in supplemental Figure 1I. (D) Schematic diagram of the CRISPR-Cas9-based mini knockout screen for the identification of genes whose knockout modifies sensitivity to crizotinib in ALCL cell lines. A crizotinib/DMSO selection pressure is applied, and gDNA is harvested on day 0 and after 14 days of treatment. The sgRNA regions are amplified from gDNA and then analyzed by next-generation sequencing, followed by statistical analyses. (E) Read counts of 6 sgRNAs targeting the indicated genes before and after a 14-day incubation with DMSO/crizotinib in the SUP-M2–derived TS cell line. Data are means ± standard deviation with read counts for individual sgRNAs (n = 6) plotted as dots. *P < .05. **P < .01, ***P < .001, unpaired Welch-corrected t test. ns, not significant.