BHQ880 improves bone disease in a murine model of human MM. SCID-hu mice were injected with INA-6 cells into the implanted bone and treated with isotype control (n = 7) or BHQ880 (n = 7) after first detection of tumor. (A) After injection of INA-6 MM cells directly into the human bone implant, serum from SCID-hu mice were monitored for production of DKK1 (blue column) and shuIL-6R (green column) by ELISA. (B) One month after treatment, bone chips were retrieved and decalcified, and sections from control and BHQ880-treated bones were immunohistochemically stained for ALP (top), and the number of OB was measured per field in isotype control and BHQ880-treated bones (bottom). Sections were observed and photographed with a Nikon transmitted light microscope. Original magnification ×200. Data are expressed as ± SD. (C) Serum level of human osteocalcin in murine blood was evaluated at the end of the treatment period by ELISA. Data are expressed as mean ± SD. (D) Sections from control and BHQ880-treated bones were stained by H&E showing increased bone tissue and decreased MM cell number in the BHQ880-treated compared with isotype control-treated samples. Sections were observed and photographed with a Nikon transmitted light microscope. Original magnification ×100.