For this, we generated bladder cancer xenografts in double-transgenic zebrafish carrying a general macrophage mCherry reporter driven by the mpeg1 promoter and a GFP reporter driven by the tnfa promoter [Tg(mpeg1:mCherry-F; tnfa:eGFP-F)] (Nguyen-Chi et al., 2017). The gene discussed is MPEG1; the disease is urinary bladder cancer.