It is noteworthy that in the small subset of CLL samples with high Myc expression we did not detect a significantly faster disease progression, despite that those cells show molecular hallmarks of Myc-transformed cells, i.e., high levels of cyclins A and E. Furthermore, in these Myc-expressing cells, p27 was found in complexes with Cdk-cyclins and Cdk2 kinase activity was efficiently inhibited. Here, CDKN1B is linked to B-cell chronic lymphocytic leukemia.