Functional assays showed that ADORA2A-AS1 facilitated ABCC2 expression in K562 and KCL22 cells via sponging miR-665, indicating that ADORA2A-AS1 may contribute to the development of imatinib resistance by driving ABCC2-mediated drug efflux in CML (198). This evidence concerns the gene ABCC2 and chronic myelogenous leukemia, BCR-ABL1 positive.