It is acknowledged that DKK-1 can stimulate the growth of prostate cancer and metastasis, whereas inhibiting the osteoblastic drive of bone formation.21, 35 Currently, the efficacy of targeting DKK-1 in multiple myeloma is proving positive in the clinical setting,36 and although therapeutic targeting of DKK-1 may have translational potential in inhibiting the growth and metastasis of solid tumors,37 further research is required to understand the molecular mechanisms that are actively involved in DKK-1 regulation. The gene discussed is DKK1; the disease is plasma cell myeloma.