By gene expression profiling, we also showed that this NOTCH1/MYC activation upregulates genes related to ribosome biogenesis such as nucleophosmin 1 (NPM1) and ribosomal proteins (RNPs), potentially conferring cell growth and/or proliferation advantages on NOTCH1-mutated CLL cells. Here, NPM1 is linked to B-cell chronic lymphocytic leukemia.