Fig. 1.

CRISPR-Cas9 genome editing efficiency and CRISPR screen results in GBC cells. a Schematic drawing of a positive screen for gemcitabine treatment using a two-vector system in NOZ cells. b A NOZ^Cas9 cell line was generated that stably expressed Flag-Cas9. c NOZ^Cas9 and control cells exhibit similar viability under gemcitabine (GEM) treatment at indicated doses. IC₅₀, 50% inhibitory concentration. d P53 protein was significantly depleted in NOZ^Cas9 cells infected with lentiviruses-delivered P53-targeting sgRNAs, followed by treatment with 1 µm doxorubicin (Dox) or vehicle for 12 h. sgNC, non-specific control sgRNA. e–g The sgRNA read counts after GEM treatment were normalized to the baseline counts in CRISPR screen and analyzed by MAGeCK software, and the results were presented as positive scores in two replicates (e), the number of good sgRNAs in two pooled replicates (f), and fold-changes in the top 10 genes exhibiting superiorly enriched sgRNAs (g). Data represent the mean ± S.D. in c (n = 3 independent experiments) and g (n = 2 independent experiments), error bars represent S.D.