CCL2 or MCP-1 is an inflammatory cytokine produced by osteoblasts, osteoclasts, tumor, endothelial, and stromal cells, and is further stimulated within the TMA by bone marrow adiposity, inflammation, and the presence of tumor cells or tumor-derived factors such as PTHrP [108,222,223,224,225]. Here, PTHLH is linked to neoplasm.