There are growing reports using nanobody-based immunotoxins to treat cancers by targeting a variety of antigens such as glypican-3, glypican-2, EGFR, HER2, VEGFR2, CD7 and CD38, which indicates the great potential of nanobody-based immunotoxins for cancer therapy [34, 57–59]. This evidence concerns the gene ERBB2 and cancer.