A role model was developed by Wu et al., who injected colon cancer cells from a patient into Tg(fli1:EGFP) transgenic zebrafish; the tumor–microenvironment interaction was observed, and a drug screening was carried, out allowing the selection of the most appropriate treatment for the patient based on the elimination of cancer cells [184]. The gene discussed is FLI1; the disease is malignant colon neoplasm.