MCR:SATB2 tumors appear grossly aggressive (Figure 1D, Figure 1—figure supplement 2C, Video 1), are invasive, and melanoma cells are frequently observed in internal organs and spreading along the spinal cord, while organ involvement is rarely observed in MCR:EGFP (Figure 1E–G, Figure 1—figure supplement 2C–F). Here, SATB2 is linked to melanoma.