HOXD13 and Ewing sarcoma: In addition, a new murine model of Shh-induced sarcoma revealed that activation of Gli1 in discrete populations of mesenchymal progenitors generated soft tissue tumors that displayed phenotypic and genotypic properties of human Ewing sarcoma, including high level expression of Hoxd13, in the absence of EWS-FLI1 [36].