Clinically, NB BM metastases have been described to be predominantly of osteolytic nature, which has been confirmed by an increase of osteoclasts in histological examinations of NB bone lesions in a xenograft mouse model [149] and osteoclast activation through upregulation of PTHrP and RANKL in NB cells that were implanted into the femur of mice [150]. This evidence concerns the gene TNFSF11 and neuroblastoma.