LOX and Ewing sarcoma: We thus genetically modified the A673 Ewing sarcoma cell line to express LOX proenzyme (A673/TR/preLOX, aminoacides 1-415), its catalytic domain (A673/TR/LOXenz, aminoacides 166-415) and the LOX propeptide (A673/TR/LOX-PP, aminoacides 1-179) in an attempt to characterize the specific contribution of full-length LOX and of each one of the LOX-derived fragments to Ewing sarcoma tumorigenesis (Figure 3A).