[摘要]：Osteosarcoma is the most common malignant primary bone tumor for which pertinent preclinical models are still needed to develop new therapeutic strategies. As osteosarcoma growth is strongly supported by bone resorption, previous studies have inhibited the cytokine receptor activator of nuclear factor-kappa B ligand using antibodies or recombinant proteins. However, its expression has not yet been inhibited using genetic approaches using small interfering RNA. To optimize the delivery of small interfering RNA to its cellular target and demonstrate their efficiency in vivo, two new osteosarcoma models expressing the firefly luciferase enzyme were developed. These luciferase-expressing osteosarcomas showed conserved osteolytic and osteogenic activities in mice and were detectable by in vivo bioluminescence imaging. In comparison with measurement of tumor volume, bioluminescence analysis enabled earlier tumor detection and revealed extensive cell death in response to ifosfamide treatment. Finally, by targeting the luciferase expression into osteosarcoma, we established a protocol for in vivo administration of small interfering RNA combined with cationic liposome. Cancer Gene Therapy (2010) 17, 387-397; doi:10.1038/cgt.2009.89; published online 15 January 2010
