Niclosamide alone resulted in a significant decrease in Sp1 in both imatinib-sensitive (K562 and KBM5) and -resistant (KBM5-T315I) CML cells, suggesting that niclosamide may inhibit the transcription of BCR-ABL gene in a Sp1-dependent manner even in T315I-BCR-ABL-positive CML cells. Here, ABL1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.