Using the whole set of soft tissue sarcomas, we found a significant inverse correlation of SIX1 with MYL9 and FBLN2, two of the mesenchymal genes most significantly downregulated in the mouse SIX1-expressing tumors, and a tendency to positive correlation with SOX2. Interestingly, the subset of myxoid liposarcomas, characterized by highly frequent SIX1 overexpression (95% of tumors), also showed strong inverse correlation between SIX1 and the mesenchymal markers MYL9 and FBLN2, although no clear correlation with SOX2 was observed in this case (Supplementary Fig. S8). This evidence concerns the gene SOX2 and soft tissue sarcoma.