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. The gene discussed is WEE1; the disease is acute lymphoblastic leukemia.