Supporting this hypothesis, previous studies have shown that PTHrP overexpression in breast cancer cells stimulates osteoblast-derived RANKL while suppressing OPG, ultimately enhancing osteoclastogenesis and bone resorption (Kitazawa and Kitazawa, 2002; Kozlow and Guise, 2005). The gene discussed is TNFRSF11B; the disease is breast carcinoma.