Bemcentinib induces apoptosis of MCL primary cells. (A) Patient–derived MCL cells were treated with dimethyl sulfoxide (DMSO) or various concentrations of bemcentinib (0-8 μM) for 24 hours. Relevant microscopy pictures revealed the presence of apoptotic cells and a reduction of the cell populations. Scale bar, 100 μM. (B-F) Cell proliferation and cell death were measured by cell counting and trypan blue staining. Experiments were performed 4 times and the mean and distribution are shown. (G) Cell death was also investigated by flow cytometry using annexin V/PI staining in patient–derived MCL cells. Bemcentinib induced apoptosis in primary MCL cells in vitro.