KDR and neoplasm: To achieve direct imaging of heterogeneous tumour cell populations in adult zebrafish, we engrafted these fluorescent transgenic ERMS by intra-muscular injection into 3-month-old adult flk1:mCherry; rag2E450fs(casper) strain zebrafish (4 × 105 cells in 2 μl per animal, Fig. 3a,b).