ERBB2 and gastric cancer: Of the many current mAbs on the market, two of them include rituximab, which is an anti-CD20 antibody that was approved by the Food and Drug Administration for treatment of B-cell non-Hodgkin lymphoma, and trastuzumab, which is an anti-HER2 receptor antibody used in the treatment of HER2-overexpressing breast and gastric cancer (McLaughlin et al., 1998; Bang et al., 2010; Slamon et al., 2011).