RANBP9 and osteosarcoma: High-grade disease is currently the best prognostic indicator of metastasis, which, in turn, is the most informative indicator of poor survival.27 Overall, all cases with negative RanBP9 or TSSC3 expression were high-grade osteosarcoma, indicating that RanBP9 and TSSC3 are reduced in high-grade osteosarcoma.