In the era of tyrosine kinase inhibitors, resistance still constitutes a problem in chronic myeloid leukemia (CML) patients, thus, new pathway-specific inhibitors like miRNAs have become important in the treatment of refractory patients. | Turkish Journal of Biology Turk J Biol (2017) 41: 926-934 © TÜBİTAK doi: Research Article Determining expression of miRNAs that potentially regulate STAT5A and 5B in dasatinib-sensitive K562 cells 1, 2 3 4 2 Asu Fergün YILMAZ *, Burçin KAYMAZ , Çağdaş AKTAN , Nur SOYER , Buket KOSOVA , 5 4 6 4 4 Ajda GÜNEŞ , Fahri ŞAHİN , Melda CÖMERT , Güray SAYDAM , Filiz VURAL 1 Department of Hematology, İzmir Kâtip Çelebi University Atatürk Training and Research Hospital, İzmir, Turkey 2 Department of Medical Biology, Ege University Hospital, İzmir, Turkey 3 Department of Medical Biology, School of Medicine, Beykent University, İstanbul, Turkey 4 Department of Hematology, Internal Medicine, Ege University Hospital, İzmir, Turkey 5 Department of Hematology, Sivas Numune Hospital, Sivas, Turkey 6 Department of Hematology, Internal Medicine, İnönü University Hospital, Malatya, Turkey Received: Accepted/Published Online: Final Version: Abstract: In the era of tyrosine kinase inhibitors, resistance still constitutes a problem in chronic myeloid leukemia (CML) patients; thus, new pathway-specific inhibitors like miRNAs have become important in the treatment of refractory patients. There are no satisfying data regarding the miRNAs and anti-miRNA treatment targeting STAT5A and 5B. In this study, we first researched the effect of dasatinib on apoptosis in the CML cell line K562. The expressions of miRNAs possibly targeting both STAT5A and 5B were then determined. The down- and upregulation of the miRNAs were compared using the ΔΔCT method. At the last stage of the study, we used a new primer probe in order to validate the results. The level of hsa-miR-940 was decreased times and the levels of hsa-miR-527 and hsa-miR-518a-5p were increased and 8 times, respectively, in the dasatinib-treated group when compared to the control group. We detected similar results in the validation
