KDR and neoplasm: Also, different nanobodies were developed against tumor molecules; some of them target the growth factor receptors such as the epidermal growth factor receptor 1, 2 (EGFR-1, 2) (25), vascular endothelial growth factor receptor-2 (VEGFR-2)(26), human epidermal growth factor receptor-2 (HER-2) (27), mesenchymal-epithelial transition factor (c-Met) (28) and chemokine receptor (29), and others target the growth factors such as hepatocyte growth factor (HGF) (30) and vascular endothelial growth factor (VEGF) (31).