In Vitro Effects of BCR-ABL Tyrosine Kinase Inhibitors on Endothelial Cells Survival and Functions

BCR-ABL tyrosine kinase inhibitors (TKIs) are the mainstay of the treatment for chronic myeloid leukemia (CML). New generation TKIs (dasatinib, nilotinib, bosutinib and ponatinib) increase the risk of arterial thromboembolism in patients with CML. Clinical data suggest that new generation TKIs might accelerate atherogenesis. This research aims to determine the effect of BCR-ABL TKIs on endothelial cell survival and major functions using an in vitro model (i.e. HUVEC). Viability was assessed using MTS and LDH assays following standard protocols. Expression of 3 adhesion molecules (i.e. ICAM-1, VCAM-1 and E-selectin) was quantified by on-cell ELISA after 4-hour TNF-α activation. Endothelial cell migration was evaluated by scratch assays (i.e. monitoring of wound closure of a scratch on confluent monolayer). At high concentration, dasatinib, nilotinib and ponatinib reduce cell metabolism. Additionally, high-dose ponatinib induces necrosis as demonstrated by increased LDH release. On-cell ELISA demonstrates decreased expression of 3 adhesion molecules (i.e. ICAM-1, VCAM-1 and E-selectin) by dasatinib, nilotinib and ponatinib at high concentration. This diminution correlates with the decreased viability of endothelial cell with these 3 treatments. Imatinib and bosutinib have no or little impact on adhesion molecule expression. Finally, scratch assays indicate that high-dose dasatinib inhibits endothelial cell migration whereas other TKIs do not have any impact. Over the 5 commercialized BCR-ABL TKIs, dasatinib, nilotinib and ponatinib possess the most impact on endothelial cells and possibly promote atherosclerosis development through impaired endothelium permeability, enabling migration and trapping of lipoprotein into the intima. Determination of mechanism(s) by which TKIs promote cardiovascular events is required to implement appropriate risk minimization measures and select patients to whom the prescription of these drugs should be avoided.