The GG genotype of the SNP309 in the MDM2 gene increases the expression of MDM2 attenuating the TP53 pathway [71], and was associated both with reduced overall survival and reduced treatment-free survival [72]; accordingly, low miR-34a levels were associated with shorter treatment-free survival and its overexpression in CLL cells induced apoptosis [59]. This evidence concerns the gene MDM2 and B-cell chronic lymphocytic leukemia.