MYC and leukemia: The expression of miR-17, miR-20a, miR-30a, miR-221, miR-222 and miR-378, which were reported to be dependent on c-Myc transcriptional activity [27, 48, 49, 50] and contribute the development of leukemia [11, 20, 21, 22], was examined in K562 cells treated with NC.