Effect of Imatinib (1microM, 24 hours) on the microRNA repertoire of chronic myeloid leukemia cell line K562

Using a microarray-based miRNA profiling, we found in a model of chronic myeloid leukemia (CML) that the activity of the oncoprotein BCR-ABL1 regulates the expression of miR-21, a "onco-microRNA" known to be overexpressed in numerous cancers. This relies on the phosphorylation status of STAT5, a transcription factor known to be activated by the kinase activity of BCR-ABL1. Mir-21 regulates the expression of PDCD4 (programmed cell death protein 4), a tumor suppressor identified here through a proteomics approach The microRNA repertoire of K562 cells having been either not treated (n=3) or treated (n=3) with the tyrosine kinase inhibitor Imatinib (1microM, 24h) was studied using Agilent microRNA V2 microarrays