Methylation of miR-3151 in CLL cells conferred resistance to apoptosis through over-expression of its direct targets MADD and PIK3R2, and hence constitutive activation of RAS/MEK/ERK and PI3K/AKT, and consequently over-expression of MCL1 (Figure 7). This evidence concerns the gene PIK3R2 and B-cell chronic lymphocytic leukemia.