This finding is in part related to del13q-, which characterizes many leukemic clones and causes the deletion of the locus encoding miR-15 and miR-16, with the function of negatively regulating bcl-2 expression, and in part due to the activation status of CLL cells, leading to the upregulation of anti-apoptotic mechanisms [140,141,142,143]. Here, BCL2 is linked to B-cell chronic lymphocytic leukemia.