The tyrosine kinase inhibitors (TKIs) such as imatinib, dasatinib and nilitinib were designed and developed for the treatment of chronic myelogenous leukemia (CML) and certain acute lymphoblastic leukemia (ALL), based on the knowledge that the protein kinase ABL is constitutively activated in patients with these disease. This evidence concerns the gene ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive.