TP53 and leukemia: Mignacca et al. reported that miRNA sponges against miR-19 and miR-155 inhibited the functions of these miRNAs and enhanced the induction of p53 and suppressor of cytokine signaling-1 (SOCS1) in human myeloma cells and mouse leukemia cells, which indicated that the antagonizing miRNA activity could reactivate the activity of cytokine-stimulated tumor suppressor pathways in leukemia cells [119].