A genome-wide CRISPR/Cas9 screen in acute myeloid leukemia cells identifies regulators of TAK-243 sensitivity

TAK-243 is a first-in-class inhibitor of ubiquitin-like modifier activating enzyme 1 (UBA1) that catalyzes ubiquitin activation, the first step in the ubiquitylation cascade. Based on its preclinical efficacy and tolerability, TAK-243 has been advanced to phase 1 clinical trials in advanced malignancies. Nonetheless, the determinants of TAK-243 sensitivity remain largely unknown. Here, we conducted a genome-wide CRISPR/Cas9 knockout screen in acute myeloid leukemia (AML) cells in the presence of TAK-243 to identify genes essential for TAK-243 action. We identified BEN domain-containing protein 3 (BEND3), a transcriptional repressor and a regulator of chromatin organization, as the top gene whose knockout confers resistance to TAK-243 A positive-selection genome-wide CRISPR/Cas9 knockout screen in OCI-AML2 cells to identify gRNAs significantly enriched in the presence of TAK-243. Specifically, cells were treated with DMSO or TAK-243 at 25 nM or 30 nM for 32 days or 36 days, followed by extraction of genomic DNA and sequencing