SU-DHL-5BCL2cDNA and UPF4DBCL2cDNA clones were less sensitive to S63845 compared to controls. Similarly, SU-DHL-5BIMdel and UPF4DBIMdel cell lines were less sensitive to S63845 compared to controls...These experiments confirmed the key role of BCL2 and BIM proteins in mediating resistance to S63846.