Instead, chondrosarcoma cell lines were positive for late chondrocyte markers such as alkaline phosphatase (ALP) activity or COL10A1 expression, both of which were strongly increased by TGF-β1 treatment, indicating activation of an abnormal differentiation program in chondrosarcoma cells (Supplementary Fig. S2b). This evidence concerns the gene TGFB1 and chondrosarcoma.