Imatinib mesylate (Imatinib, IMA), a small molecule inhibitor of tyrosine kinase (TKI), has been approved for the treatment of BCR-ABL positive leukemia and gastrointestinal stromal tumors (GIST), which has dramatically improved the clinical outcome of those cancers [12, 13]. Here, ABL1 is linked to gastrointestinal stromal tumor.