TNFRSF11B and chronic kidney disease: Several CKD-BMD biomarkers, such as fetuin-A, osteoprotegerin (OPG), osteopontin, fibroblast growth factor-23 (FGF-23), receptor activator of nuclear factor-κB ligand (RANKL), klotho or bone morphogenetic protein 7 (BMP-7) have been associated with vascular calcification [5, 6].