MMPs, which play essential roles in the degradation and remodeling of extracellular matrix, can be stimulated by pro-inflammatory cytokines such as IL-6 to be produced in fibroblasts, macrophages, synovial cells and chondrocytes.16 Particularly, MMP-3 may participate in the onset of inflammation and osteoporosis, and predominantly regulate bone destruction. The gene discussed is IL6; the disease is osteoporosis.