We recently investigated the MIR34-family in a cohort of 150 primary DLBCL patients, and identified promoter methylation, and hence inactivation, of MIR34A in 28 % of the patients, and thereby showed that concomitant (”double hit”) TP53 mutation and MIR34A methylation were related to an exceedingly poor median survival of only 9.4 months [4, 20]. This evidence concerns the gene MIR34A and diffuse large B-cell lymphoma.