CDH17 and neoplasm: This limited accessibility of CDH17 outside of tumor cells, which exhibit high CDH17 expression throughout their cell surface, may explain why drugs have difficulty accessing CDH17 in normal intestinal epithelia (Figure S11, Supporting Information).[12c] Although CDH17 targeting has gained attention in recent years, most studies have focused on conventional monoclonal antibodies, Fab or scFv fragments for drug development.[12, 36] The exploration of nanobodies specifically targeting CDH17 has been limited.