For figure 7, we generated primary sarcomas in Col1a1FRT-STOP-FRT-Cre-ER-T2; KrasFRT-STOP-FRT-G12D/+; p53FRT/FRT; Rosa26mTmG/+ mice with intramuscular Adeno-FlpO and attempted to activate eGFP expression in tumors by injecting the mice with intraperitoneal (IP) tamoxifen. This evidence concerns the gene FLT1 and sarcoma.