CagA binds, in a phosphorylation-dependent or phosphorylation-independent manner, to a range of host proteins including Src homology 2 (SH2)-containing tyrosine phosphatase 2 (SHP-2) [13], growth factor receptor-bound protein 2 (Grb2) [14], C-terminal Src kinase (Crk) [15] and microtubule affinity-regulating kinase 2 (MARK2) [16], resulting in dysregulation of key cellular biochemical pathways, apoptosis, and the multi-step development of gastric cancer [13,17,18]. Here, GRB2 is linked to gastric cancer.