Nilotinib activates endothelial TLR4 to exacerbate atherosclerosis

The use of nilotinib (Tasigna®), a second-generation tyrosine kinase inhibitor for treating chronic myeloid leukemia, increases risks for atherosclerosis. Here, we demonstrate that in endothelial cells, nilotinib activated TLR4, triggerd expression of inflammatory molecules, and increased monocyte attachment, which were all inhibited by knockdown of TLR4 or TLR4 inhibitor, CLI-095. Orally administered nilotinib profoundly accelerated atherosclerotic lesion formation in ApoE −/− mice, while co-administration of CLI-095 effectively reduced lesion areas. Our findings reveal TLR4 activation as an underlying mechanism of the pro-atherosclerotic effect of nilotinib and suggest TLR4 inhibition as an effective therapeutic approach to address vascular safety issue of nilotinib.