HSP90AB1 and cancer: Supporting this conclusion, three monoclonal antibodies targeting different regions of Hsp90—1G6-D7 (linker region), 4c5 (N-terminal), and SPA-830 (C-terminal region)—have each been shown to strongly block eHsp90-driven migration of both normal and cancer cells, as well as tumor formation and metastasis in mouse models [22,24,26].