%0 Journal Article
%T Imatinib: A Breakthrough of Targeted Therapy in Cancer
%A Nida Iqbal
%A Naveed Iqbal
%J Chemotherapy Research and Practice
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/357027
%X 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. This paper is a comprehensive review of the role of Imatinib in oncology. 1. Introduction Imatinib (also known as ˇ°Gleevecˇ± or ˇ°Glivecˇ±), a tyrosine kinase inhibitor, was called as ˇ°magical bullet,ˇ± when it revolutionized the treatment of chronic myeloid leukemia (CML) in 2001. Imatinib was invented in the late 1990s by biochemist Nicholas Lyndon then working for Ciba-Geigy (now Novartis), and its use to treat CML was driven by Brian Druker, an oncologist at the Dana-Farber Institute. The first clinical trial of Imatinib took place in 1998 and the drug received FDA approval in May 2001. Lyndon, Druker, and the other colleagues were awarded the Lasker-DeBakey Clinical Medical Research Award in 2009 for ˇ°converting a fatal cancer into a manageable conditionˇ± and the Japan Prize in 2012 for their part in ˇ°the development of a new therapeutic drug targeting cancer-specific molecules.ˇ± Encouraged by the success of Imatinib in treating CML patients, scientists explored its effect in other cancers and it was found to produce a similar miracle effect in other cancers where tyrosine kinases were overexpressed. This review discusses the clinical implications of Imatinib in various cancers. 2. Clinical Pharmacology Tyrosine kinases are important mediators of the signaling cascade, determining key roles in diverse biological processes like growth, differentiation, metabolism, and apoptosis in response to external and internal stimuli. Deregulation of protein kinase activity has been shown to play a central role in the pathogenesis of human cancers. Imatinib, a 2-phenyl amino pyrimidine derivative, is a tyrosine kinase inhibitor with activity against ABL, BCR-ABL, PDGFRA, and c-KIT. The active sites of tyrosine kinases each have a binding site for ATP. The enzymatic activity catalyzed by a tyrosine kinase is the
%U http://www.hindawi.com/journals/cherp/2014/357027/