TP53 and sarcoma: Mice harboring a latent copy of oncogenic KrasLSLG12D (silenced by a floxed “loxP-stop-loxP” (LSL) cassette) and two floxed p53 alleles (p53FlΔ2-10) that were simultaneously activated to express mutant KrasG12D and delete p53 following injection of adenoviral-Cre into the muscle, rapidly developed sarcomas with significant metastatic potential.