Essentiality of IMiD effectors across PEL cell lines. Median significance of essentiality of all genes screened by the Brunello sgRNA library across 8 PEL cell lines. Genes are ranked using median P value scores. The position of genes that have been implicated in IMiD action is indicated in blue, including the IMiD target CRBN, neosubstrates IKZF1, IKZF3, CSNK1A1, and ZFP91, and downstream effectors IRF4 and MYC. Only IRF4, MYC, and CSNK1A1 score as essential across PEL cell lines.