Moreover, a decrease in PG1 cell-derived tumor growth was observed only in the Rankl-/- mice (Figure S5), reinforcing the importance of the vicious cycle in the growth of osteosarcoma (extrinsic, Figure 6), but also raising the question of other extrinsic implications of RANKL than osteoclastogenesis control. The gene discussed is TNFSF11; the disease is osteosarcoma.