As the Grb2 binding site at Tyr177 in BCR is uniformly conserved among other BCR-fusion proteins, such as BCR-JAK2, BCR-PDGFRA, BCR-RET and BCR-NTRK2, our results suggest that Shp2 and Gab1 play an equally important role in cancers driven by these oncogenes as well. Here, GRB2 is linked to cancer.