SNIPER(ABL)-39 showed growth-inhibitory and protein knockdown effects in BCR-ABL-positive CML cell lines, such as KCL-22 (IC50 = 8.06 nM) and KU-812 (IC50 = 6.72 nM), but did not impact the growth of BCR-ABL-negative leukaemia lines like HL-60, MOLT-4, and Jurkat. This evidence concerns the gene BCR and chronic myelogenous leukemia, BCR-ABL1 positive.