GLEEVEC (IMATINIB): A BREAKTHROUGH IN CANCER TREATMENT

Deregulated protein tyrosine kinase activity is central to the pathogenesis of human cancers. Targeted therapy in the form of selective tyrosine kinase inhibitors (TKIs) has transformed the approach to management of various cancers and represents a therapeutic breakthrough. Imatinib was one of the first cancer therapies to show the potential for such targeted action. Imatinib, an oral targeted therapy, inhibits tyrosine kinases specifically BCR-ABL, c-KIT, and PDGFRA. Apart from its remarkable success in CML and GIST, Imatinib benefits various other tumors caused by Imatinib-specific abnormalities of PDGFR and c-KIT. Imatinib has also been proven to be effective in steroid-refractory chronic graft-versus-host disease because of its anti-PDGFR action. Gleevec has been approved for the treatment of patients with positive inoperable and/or metastatic malignant gastrointestinal stromal tumors (GISTs). Gleevec is a signal transduction inhibitor that works by targeting the activity of enzymes called tyrosine kinases. The activity of one of these tyrosine kinases, known as c-kit, is thought to drive the growth and division of most GISTs. Keywods: tyrosine kinase inhibitors (TKIs), Gleevec, metastatic malignant gastrointestinal stromal tumors (GISTs).