NCIt definition : An antineoplastic agent that inhibits the Bcr-Abl fusion protein tyrosine kinase,
an abnormal enzyme produced by chronic myeloid leukemia cells that contain the Philadelphia
chromosome. Imatinib also inhibits the receptor tyrosine kinases for platelet-derived
growth factor (PDGF) and stem cell factor (SCF)/c-kit; the SCF/c-kit receptor tyrosine
kinase is activated in gastrointestinal stromal tumor (GIST). This agent inhibits
proliferation and induces apoptosis in cells that overexpress these oncoproteins.;