Moreover, tumors formed by SiRb‐OeMyc cells were positive for ALP, osteonectin, and osteocalcin, heterogeneously positive for desmin and α‐SMA, the sarcoma marker, and negative for FLI‐1, S100, PPARγ, and h‐caldesmon, excluding the possibility of Ewing sarcoma, chondrosarcoma, liposarcoma, and leiomyosarcoma. This evidence concerns the gene SPARC and chondrosarcoma.