MCL1 and mantle cell lymphoma: Unfortunately, B‐cells are notoriously difficult to transfect, and only a limited number of studies have reported on short interfering RNA (siRNA) delivery to lymphoma cells.23, 24, 25, 26, 27 For example, we have previously described the ability of siRNA‐loaded lipid nanoparticles (LNPs) to silence Mcl‐1 expression and increase the apoptosis rates of mantle cell lymphoma.28 Because our LNPs are potent transfection agents,29, 30, 31, 32, 33 we herein investigate their use for multiplexed gene silencing in mantle cell lymphoma cells.