Fig. 4

Signal transduction pathway of the BCR-ABL fusion gene and Imatinib action. Imatinib selectively inhibits the tyrosine kinase activity that is responsible for the signaling pathway illustrated through tyrosine kinase phosphorylation of these interactions. Main signaling pathways associated with the oncogenic activity of the BCR-ABL gene is MYC, RAS, MAPK, STAT and PI3K. These pathways result in the inhibition of gene transcription, mitochondrial processing of apoptotic reactions and cytoskeletal organization culminating in an increase in abnormal cell activities including unimpeded proliferation, angiogenesis and enhanced cell survival. When Imatinib binds to the tyrosine kinase receptor it in turn deactivates these pathways resulting in cell death of the mutated leukemic cell (produced with Microsoft^® PowerPoint^®) [9,10,11, 33]