JNJ-75276617 exhibits potent antiproliferation activity in MEN1-mutant cell lines resistant to other menin-KMT2A inhibitors. (A) Fluorescence polarization assay demonstrating the dose-dependent displacement of a KMT2A peptide from WT, M327I-mutant, and T349M-mutant menin on treatment with JNJ-75276617. Data are represented as mean ± standard deviation (SD), n = 3 independent replicates. (B) Evaluation of JNJ-75276617 for antiproliferation activity in MEN1^M327I and MEN1^T349M mutant KMT2A-r MV4-11 cell lines. Drug response was calculated on the basis of the luminescence for each menin inhibitor concentration relative to the DMSO sample after 10 days of JNJ-75276617 treatment. Data are represented as mean ± SD, n = 3 independent experiments. (C) Superimposition of a docking model of JNJ-75276617 (green sticks; docked on M327I-mutant menin chain A; Protein Data Bank Identifier [PDB] ID: 8E90; second rotamer of W346 [chain B] is displayed in gray lines). JNJ-75276617 bound to wild-type menin (this study; PDB ID: in deposition) is shown for reference in orange and its binding pocket as gray surface. Side chain of M327/I327 is shown as sticks. The distance between selected atoms of T349 and JNJ-75276617 is shown as orange dashed line. Residue numbering is according to transcript variant: NM_000244.