Studies from our laboratory demonstrated that the transition of CML to lymphoid blast crisis (LBC) in mice requires the presence of Lyn, Hck, and Fgr [23], and Donato et al. showed that overexpression and/or activation of Hck and Lyn occur during CML progression [21]. This evidence concerns the gene LYN and chronic myelogenous leukemia, BCR-ABL1 positive.