HS-27, a fluorescent Hsp90 inhibitor, detects Hsp90 expression on the surface of intact tissue specimens. It consists of the core elements of SNX-5422, an Hsp90 inhibitor linked via a PEG linker to a fluorescein derivative (fluorescein isothiocyanate or FITC) that binds to peripherally expressed Hsp90 combine.
HS-27 labels all receptor subtypes of breast cancer, but not normal cells, and specifically binds to Hsp90 expressed on the surface of breast cancer cells before being internalized.
