Previous findings showed that Parathyroid hormone-related protein (PTHrP), receptor activator of nuclear factor-κB ligand (RANKL) and interleukin (IL)-11, IL-8, IL-6, etc, produced by metastatic cancer cells, are involved in osteolytic bone metastases (23). The gene discussed is CXCL8; the disease is metastatic malignant neoplasm.