POU2AF1 and diffuse large B-cell lymphoma: OCAB is crucial for GC formation, and previous lethality CRISPR screens showed that it is essential for DLBCL viability.12,13 To globally identify regulators of OCAB expression, knock-in mO-OCAB cells were transduced with the sgRNA Brunello library, which targets all human protein-coding genes with up to 4 sgRNAs.14 Ten days post-infection, the top and bottom 5% mOlow and mOhigh cells were sorted, and sgRNA enrichment was determined by deep sequencing.