In CML, constitutive RAS activation is promoted by BCR-ABL1 interaction with Grb2 (Growth factor receptor bound protein), SOS (Son Of Sevenless) and Gab2 (Grb2-associated binder 2) and plays a critical role in leukemogenesis [2, 40] (Fig. 1a). This evidence concerns the gene GAB2 and chronic myelogenous leukemia, BCR-ABL1 positive.