Indeed, blocking the Wnt-signaling inhibitor dickkopf-1 (DKK1) with a neutralizing antibody [16], or stimulating Wnt signaling in myelomatous bones by using lithium chloride [17] or Wnt3a [18] resulted in stimulating bone formation and reducing bone loss and myeloma cell growth in vivo. Here, DKK1 is linked to plasma cell myeloma.