GUCY2C and neoplasm: • Generation of anti-GCC antibodies and conjugation to DGN549• Flow cytometry• In vitro cytotoxicity assay• Human xenograft tumor studies in mice• HEK-293 GCC cells or human primary tumors in DMEM were injected to mice• Pharmacokinetics analysis• Immunohistochemistry• 89Zr-immuno PET imaging